Astronomers detect first Earth-size planets orbiting another star
By Brian Vastag, Published: December 20 - Washington Post
In a milestone hailed by scientists as a key step toward finding another Earth-like world, astronomers Tuesday announced the discovery of two blazingly hot planets roughly the size of Earth some 950 light years distant.
The discovery “demonstrates for first time that Earth-size planets exist around other stars, and that we can detect them,” said Francois Fressin, an astronomer at the Harvard-Smithsonian Center for Astrophysics who led the discovery team.
The two planets orbit a star much like our sun, but they whiz around it so fast and so close that their surfaces sizzle like frying pans.
“They’re way too hot to be anything like our own Earth,” said Sara Seager, a planet hunter at the Massachusetts Institute of Technology and a member of the discovery team.
The implication: No life — at least life as we can conceive it — is possible on the new planets.
Still, finding these hot Earth-sized planets is “seriously cool,” said Lisa Kaltenegger, who studies so-called exoplanets at the Max Planck Institute in Heidelberg, Germany, and was not involved in the research. “These discoveries are a great technological step forward.”
The planets were announced Tuesday in the journal Nature and during a NASA teleconference.
Detected by NASA’s Kepler space telescope, the two planets, dubbed Kepler 20e and Kepler 20f, are almost certainly rocky like Earth and not gaseous like Jupiter, Kaltenegger said.
The smaller planet, Kepler 20e, is about the size of Venus but much closer to its star, zooming around it every six days. An Earth year, by contrast, is 365 days.
The larger planet, Kepler 20f, is just three percent larger than Earth. “It’s the first Earth-sized planet” ever detected orbiting another star, Seager said. “It is a big milestone.”
Kepler 20f is a bit farther out from its star, completing an orbit about every 20 days. Its surface temperature is hotter than a pizza oven — about 800 degrees Fahrenheit.
The two planets nestle in among three other larger planets tightly circling the star Kepler 20.
“It’s a beautiful planetary system,” said Dimitar Sasselov, a planet hunter at the Harvard-Smithsonian center and a member of the discovery team.
But it’s also a puzzling one. None of the five planets lie within the so-called habitable zone, the narrow band of space around a star where water can exist as liquid. Instead, all five planets hug their star, orbiting closer than Mercury is to the sun.
And, unlike our solar system, the two newly-found rocky planets are interspersed with three larger, gassy, Neptune-like planets.
“The architecture of that solar system is crazy,” said David Charbonneau of Harvard University. “In our solar system, the two different kinds of planets don’t mingle. This is the first time we’ve seen anything like this.”
The finds mark a key moment in the accelerating search to bag and tag planets outside our solar system. Since the first such detection in 1995, multiple teams employing ground and space telescopes have found more than 700 planets orbiting other stars, according to an online catalogue.
The message, says Seager, is simple: Planets abound wherever we look. “We think every star has planets,” she said.
NASA launched the $600 million Kepler space telescope in 2009 on a mission to find other Earth-like planets. So far, the telescope has found 33 confirmed planets and 2,326 possible planets, but they are all too big or too hot to qualify as Earth-like. The telescope detects planets by staring at 150,000 stars near the constellation Cygnus. When light from a star dims, or winks, it indicates a possible planet passing by. If Kepler sees the same wink three times, astronomers infer a planet. The time that passes between winks indicates the planet’s orbital period, or year.
Earlier this month, Kepler scientists announced a planet square in its star’s habitable zone. Dubbed Kepler 22b, that planet is about 1.4 times as wide as Earth, likely too large to host a rocky surface. “It’s too big, we think, for life,” Seager said.
The next milestone for Kepler will be the big one: The detection of an Earth-sized world with a surface temperature just right for life. Kepler scientists are confident they will soon spot such an Earth 2.0.
“One of these days — whether next year or two years from now — Kepler will confirm a true Earth analog,” Sasselov said. “And that will be a historic moment.”
When asked whether the Kepler team planned to give the newly found Earth-sized planets a catchier name, Sasselov balked. “Everybody wants pretty names,” he said. “But what do we do? There will be thousands of these planets.”
Wednesday, December 21, 2011
Saturday, December 10, 2011
Higgs boson "the God particle" getting closer
Higgs particle: Getting closer
By Joel Achenbach
The Higgs particle is also known as the Higgs boson, or “the God particle,” a term that Leon Lederman used some years ago and which delighted journalists but surely offended photons and electrons throughout the universe. The Higgs is named after Peter Higgs, a theorist who four decades ago predicted its existence as part of the Standard Model of particle physics. No one’s ever found one. Discovering the Higgs is a central purpose of two very elaborate experiments being conducted at the Large Hadron Collider at CERN. On Tuesday, the CERN scientists will announce their latest batch of results, and, as Scientific American has reported, rumors abound that they’ve homing in on the Higgs. More here from Nature.
CERN has itself said that there will be no “discovery” announcement, and the best bet is that the two experiments haven’t quite nailed the Higgs with certainty but are getting very close. “I am looking for closure, and I don’t expect to get it next week,” a leading theorist tells me by email.
As SciAm notes, certainty in this case is made difficult by the fact that, even with the elaborate infrastructure in place at the LHC, there’s no way to catch a Higgs and bottle it up like a lightning bug.
“...the CMS and ATLAS detectors cannot directly catch Higgs bosons; those particles would decay into other particles immediately after being created in the LHC’s proton collisions. Instead, physicists must analyze the subatomic debris from the decays and reconstruct what happened.”
As my editor, Claudia, has pointed out, we’re at a point where a lot of major discoveries are indirect. No one shouts “Land ho!” from the crow’s nest anymore. Instead we find planets like Kepler 22-b, utterly invisible even with the most advanced telescope, but found through fluctuations in the light of its parent star. We are devising new ways to peel back layers of the onion.
Physicists are hoping to discover some “new physics” with the LHC. At the very least, they’d like to find a new particle they hadn’t even imagined. The Higgs, however, is kind of a familiar particle, as undiscovered particles go. It’s supposed to be lurking there somewhere because otherwise the Standard Model has a gaping hole in it. What matters most about the Higgs, beyond whether it exists at all, is how massive it is. If it’s high-mass, that gives you a different universe than a low-mass Higgs. Among other things, the “stability” of the vacuum is in play. A low-mass Higgs leads to a less stable vacuum, is what I hear.
I hope that we can all agree that a stable vacuum is better than an unstable one. We’ve got enough problems.
By Joel Achenbach | 10:15 AM ET, 12/10/2011
By Joel Achenbach
The Higgs particle is also known as the Higgs boson, or “the God particle,” a term that Leon Lederman used some years ago and which delighted journalists but surely offended photons and electrons throughout the universe. The Higgs is named after Peter Higgs, a theorist who four decades ago predicted its existence as part of the Standard Model of particle physics. No one’s ever found one. Discovering the Higgs is a central purpose of two very elaborate experiments being conducted at the Large Hadron Collider at CERN. On Tuesday, the CERN scientists will announce their latest batch of results, and, as Scientific American has reported, rumors abound that they’ve homing in on the Higgs. More here from Nature.
CERN has itself said that there will be no “discovery” announcement, and the best bet is that the two experiments haven’t quite nailed the Higgs with certainty but are getting very close. “I am looking for closure, and I don’t expect to get it next week,” a leading theorist tells me by email.
As SciAm notes, certainty in this case is made difficult by the fact that, even with the elaborate infrastructure in place at the LHC, there’s no way to catch a Higgs and bottle it up like a lightning bug.
“...the CMS and ATLAS detectors cannot directly catch Higgs bosons; those particles would decay into other particles immediately after being created in the LHC’s proton collisions. Instead, physicists must analyze the subatomic debris from the decays and reconstruct what happened.”
As my editor, Claudia, has pointed out, we’re at a point where a lot of major discoveries are indirect. No one shouts “Land ho!” from the crow’s nest anymore. Instead we find planets like Kepler 22-b, utterly invisible even with the most advanced telescope, but found through fluctuations in the light of its parent star. We are devising new ways to peel back layers of the onion.
Physicists are hoping to discover some “new physics” with the LHC. At the very least, they’d like to find a new particle they hadn’t even imagined. The Higgs, however, is kind of a familiar particle, as undiscovered particles go. It’s supposed to be lurking there somewhere because otherwise the Standard Model has a gaping hole in it. What matters most about the Higgs, beyond whether it exists at all, is how massive it is. If it’s high-mass, that gives you a different universe than a low-mass Higgs. Among other things, the “stability” of the vacuum is in play. A low-mass Higgs leads to a less stable vacuum, is what I hear.
I hope that we can all agree that a stable vacuum is better than an unstable one. We’ve got enough problems.
By Joel Achenbach | 10:15 AM ET, 12/10/2011
Friday, November 18, 2011
Neutrinos Faster Than Light
Second experiment confirms faster-than-light particles
By Brian Vastag, Published: November 17
Washington Post
A second experiment at the European facility that reported subatomic particles zooming faster than the speed of light — stunning the world of physics — has reached the same result, scientists said late Thursday.
The “positive outcome of the [second] test makes us more confident in the result,” said Fernando Ferroni, president of the Italian Institute for Nuclear Physics, in a statement released late Thursday. Ferroni is one of 160 physicists involved in the international collaboration known as OPERA (Oscillation Project with Emulsion Tracking Apparatus) that performed the experiment.
While the second experiment “has made an important test of consistency of its result,” Ferroni added, “a final word can only be said by analogous measurements performed elsewhere in the world.”
That is, more tests are needed, and on other experimental setups. There is still a large crowd of skeptical physicists who suspect that the original measurement done in September was an error.
Should the results stand, they would upend more than a century of modern physics.
In the first round of experiments, a massive detector buried in a mountain in Gran Sasso, Italy, recorded neutrinos generated at the CERN particle accelerator on the French-Swiss border arriving 60 nanoseconds sooner than expected. CERN is the French acronym for European Council for Nuclear Research.
A chorus of critiques from physicists soon followed. Among other possible errors, some suggested that the neutrinos generated at CERN were smeared into bunches too wide to measure precisely.
So in recent weeks, the OPERA team tightened the packets of neutrinos that CERN sent sailing toward Italy. Such tightening removed some uncertainty in the neutrinos’ speed.
The detector still saw neutrinos moving faster than light.
“One of the eventual systematic errors is now out of the way,” said Jacques Martino, director of the National Institute of Nuclear and Particle Physics in France, in a statement.
But the faster-than-light drama is far from over, Martino added. The OPERA team is discussing more cross-checks, he added, including possibly running a fiber the 454 miles between the sites.
For more than a century, the speed of light has been locked in as the universe’s ultimate speed limit. No experiment had seen anything moving faster than light, which zips along at 186,000 miles per second.
Much of modern physics — including Albert Einstein’s famous theory of relativity — is built on that ultimate speed limit.
The scientific world stopped and gaped in September when the OPERA team announced it had seen neutrinos moving just a hint faster than light.
“If it’s correct, it’s phenomenal,” said Rob Plunkett, a scientist at Fermilab, the Department of Energy physics laboratory in Illinois, in September. “We’d be looking at a whole new set of rules” for how the universe works.
By Brian Vastag, Published: November 17
Washington Post
A second experiment at the European facility that reported subatomic particles zooming faster than the speed of light — stunning the world of physics — has reached the same result, scientists said late Thursday.
The “positive outcome of the [second] test makes us more confident in the result,” said Fernando Ferroni, president of the Italian Institute for Nuclear Physics, in a statement released late Thursday. Ferroni is one of 160 physicists involved in the international collaboration known as OPERA (Oscillation Project with Emulsion Tracking Apparatus) that performed the experiment.
While the second experiment “has made an important test of consistency of its result,” Ferroni added, “a final word can only be said by analogous measurements performed elsewhere in the world.”
That is, more tests are needed, and on other experimental setups. There is still a large crowd of skeptical physicists who suspect that the original measurement done in September was an error.
Should the results stand, they would upend more than a century of modern physics.
In the first round of experiments, a massive detector buried in a mountain in Gran Sasso, Italy, recorded neutrinos generated at the CERN particle accelerator on the French-Swiss border arriving 60 nanoseconds sooner than expected. CERN is the French acronym for European Council for Nuclear Research.
A chorus of critiques from physicists soon followed. Among other possible errors, some suggested that the neutrinos generated at CERN were smeared into bunches too wide to measure precisely.
So in recent weeks, the OPERA team tightened the packets of neutrinos that CERN sent sailing toward Italy. Such tightening removed some uncertainty in the neutrinos’ speed.
The detector still saw neutrinos moving faster than light.
“One of the eventual systematic errors is now out of the way,” said Jacques Martino, director of the National Institute of Nuclear and Particle Physics in France, in a statement.
But the faster-than-light drama is far from over, Martino added. The OPERA team is discussing more cross-checks, he added, including possibly running a fiber the 454 miles between the sites.
For more than a century, the speed of light has been locked in as the universe’s ultimate speed limit. No experiment had seen anything moving faster than light, which zips along at 186,000 miles per second.
Much of modern physics — including Albert Einstein’s famous theory of relativity — is built on that ultimate speed limit.
The scientific world stopped and gaped in September when the OPERA team announced it had seen neutrinos moving just a hint faster than light.
“If it’s correct, it’s phenomenal,” said Rob Plunkett, a scientist at Fermilab, the Department of Energy physics laboratory in Illinois, in September. “We’d be looking at a whole new set of rules” for how the universe works.
Tuesday, March 1, 2011
HP Rethinking the Modern Computer
February 28, 2011
Remapping Computer Circuitry to Avert Impending Bottlenecks
By JOHN MARKOFF
PALO ALTO, Calif. — Hewlett-Packard researchers have proposed a fundamental rethinking of the modern computer for the coming era of nanoelectronics — a marriage of memory and computing power that could drastically limit the energy used by computers.
Today the microprocessor is in the center of the computing universe, and information is moved, at heavy energy cost, first to be used in computation and then stored. The new approach would be to marry processing to memory to cut down transportation of data and reduce energy use.
The semiconductor industry has long warned about a set of impending bottlenecks described as “the wall,” a point in time where more than five decades of progress in continuously shrinking the size of transistors used in computation will end. If progress stops it will not only slow the rate of consumer electronics innovation, but also end the exponential increase in the speed of the world’s most powerful supercomputers — 1,000 times faster each decade.
However, in an article published in IEEE Computer in January, Parthasarathy Ranganathan, a Hewlett-Packard electrical engineer, offers a radical alternative to today’s computer designs that would permit new designs for consumer electronics products as well as the next generation of supercomputers, known as exascale processors.
Today, computers constantly shuttle data back and forth among faster and slower memories. The systems keep frequently used data close to the processor and then move it to slower and more permanent storage when it is no longer needed for the ongoing calculations.
In this approach, the microprocessor is in the center of the computing universe, but in terms of energy costs, moving the information, first to be computed upon and then stored, dwarfs the energy used in the actual computing operation.
Moreover, the problem is rapidly worsening because the amount of data consumed by computers is growing even more quickly than the increase in computer performance.
“What’s going to be the killer app 10 years from now?” asked Dr. Ranganathan. “It’s fairly clear it’s going to be about data; that’s not rocket science. In the future every piece of storage on the planet will come with a built-in computer.”
To distinguish the new type of computing from today’s designs, he said that systems will be based on memory chips he calls “nanostores” as distinct from today’s microprocessors. They will be hybrids, three-dimensional systems in which lower-level circuits will be based on a nanoelectronic technology called the memristor, which Hewlett-Packard is developing to store data. The nanostore chips will have a multistory design, and computing circuits made with conventional silicon will sit directly on top of the memory to process the data, with minimal energy costs.
Within seven years or so, experts estimate that one such chip might store a trillion bytes of memory (about 220 high-definition digital movies) in addition to containing 128 processors, Dr. Ranganathan wrote. If these devices become ubiquitous, it would radically reduce the amount of information that would need to be shuttled back and forth in future data processing schemes.
For years, computer architects have been saying that a big new idea in computing was needed. Indeed, as transistors have continued to shrink, rather than continuing to innovate, computer designers have simply adopted a so-called “multicore” approach, where multiple processors are added as more chip real estate became available.
The absence of a major breakthrough was referred to in a remarkable confrontation that took place two years ago during Hot Chips, an annual computer design conference held each summer at Stanford University.
John L. Hennessy, the president of Stanford and a computer design expert, stood before a panel of some of the world’s best computer designers and challenged them to present one fundamentally new idea. He was effectively greeted with silence.
“What is your one big idea?” he asked the panel. “I believe that the next big idea is going to come from someone who is considerably younger than the average age of the people in this room.”
Dr. Ranganathan, who was 36 at the time, was there. He said that he took Dr. Hennessy’s criticism as an inspiration for his work and he believes that nanostore chip design is an example of the kind of big idea that has been missing.
It is not just Dr. Hennessy who has been warning about the end the era of rapidly increasing computer performance. In 2008, Darpa, the Defense Advanced Research Projects Agency assembled a panel of the nation’s best supercomputer experts and asked them to think about ways in which it might be possible to reach an exascale computer — a supercomputer capable of executing one quintillion mathematical calculations in a second, about 1,000 times faster than today’s fastest systems.
The panel, which was led by Peter Kogge, a University of Notre Dame supercomputer designer, came back with pessimistic conclusions. “Will the next decade see the same kind of spectacular progress as the last two did?” he wrote in the January issue of IEEE Spectrum. “Alas, no.” He added: “The party isn’t over, but the police have arrived and the music has been turned way down.”
One reason is computing’s enormous energy appetite. A 10-petaflop supercomputer — scheduled to be built by I.B.M. next year — will consume 15 megawatts of power, roughly the electricity consumed by a city of 15,000 homes. An exascale computer, built with today’s microprocessors, would require 1.6 gigawatts. That would be roughly one and half times the amount of electricity produced by a nuclear power plant.
The panel did, however, support Dr. Ranganathan’s memory-centric approach. It found that the energy cost of a single calculation was about 70 picojoules (a picojoule is one millionth of one millionth of a joule. The energy needed to keep a 100-watt bulb lit for an hour is more than eight million joules). However, when the energy costs of moving the data needed to do a single calculation — moving 200 bits of data in and out of memory multiple times — the real energy cost of a single calculation might be anywhere from 1,000 to 10,000 picojoules.
A range of other technologies are being explored to allow the continued growth of computing power, including ways to build electronic switches smaller than 10 nanometers — thought to be the minimum size for current chip-making techniques.
Last month, for example, researchers at Harvard and Mitre Corporation reported the development of nanoprocessor “tiles” based on electronic switches fabricated from ultrathin germanium-silicon wires.
I.B.M. researchers have been pursuing so-called phase-change memories based on the ability to use an electric current to switch a material from a crystalline to an amorphous state and back again. This technology was commercialized by Samsung last year. More recently, I.B.M. researchers have said that they are excited about the possibility of using carbon nanotubes as an a partial step to build hybrid systems that straddle the nanoelectronic and microelectronic worlds.
Veteran computer designers note that whichever technology wins, the idea of moving computer processing closer to memory has been around for some time, and it may simply be the arrival of nanoscale electronics that finally makes the new architecture possible.
An early effort was called iRAM, in a research project at the University of California, Berkeley, during the late 1990s. Today pressure for memory-oriented computing is coming both from computing challenges posed by smartphones and from the data center, said Christoforos Kozyrakis, a Stanford University computer scientist who worked on the iRAM project in graduate school.
Remapping Computer Circuitry to Avert Impending Bottlenecks
By JOHN MARKOFF
PALO ALTO, Calif. — Hewlett-Packard researchers have proposed a fundamental rethinking of the modern computer for the coming era of nanoelectronics — a marriage of memory and computing power that could drastically limit the energy used by computers.
Today the microprocessor is in the center of the computing universe, and information is moved, at heavy energy cost, first to be used in computation and then stored. The new approach would be to marry processing to memory to cut down transportation of data and reduce energy use.
The semiconductor industry has long warned about a set of impending bottlenecks described as “the wall,” a point in time where more than five decades of progress in continuously shrinking the size of transistors used in computation will end. If progress stops it will not only slow the rate of consumer electronics innovation, but also end the exponential increase in the speed of the world’s most powerful supercomputers — 1,000 times faster each decade.
However, in an article published in IEEE Computer in January, Parthasarathy Ranganathan, a Hewlett-Packard electrical engineer, offers a radical alternative to today’s computer designs that would permit new designs for consumer electronics products as well as the next generation of supercomputers, known as exascale processors.
Today, computers constantly shuttle data back and forth among faster and slower memories. The systems keep frequently used data close to the processor and then move it to slower and more permanent storage when it is no longer needed for the ongoing calculations.
In this approach, the microprocessor is in the center of the computing universe, but in terms of energy costs, moving the information, first to be computed upon and then stored, dwarfs the energy used in the actual computing operation.
Moreover, the problem is rapidly worsening because the amount of data consumed by computers is growing even more quickly than the increase in computer performance.
“What’s going to be the killer app 10 years from now?” asked Dr. Ranganathan. “It’s fairly clear it’s going to be about data; that’s not rocket science. In the future every piece of storage on the planet will come with a built-in computer.”
To distinguish the new type of computing from today’s designs, he said that systems will be based on memory chips he calls “nanostores” as distinct from today’s microprocessors. They will be hybrids, three-dimensional systems in which lower-level circuits will be based on a nanoelectronic technology called the memristor, which Hewlett-Packard is developing to store data. The nanostore chips will have a multistory design, and computing circuits made with conventional silicon will sit directly on top of the memory to process the data, with minimal energy costs.
Within seven years or so, experts estimate that one such chip might store a trillion bytes of memory (about 220 high-definition digital movies) in addition to containing 128 processors, Dr. Ranganathan wrote. If these devices become ubiquitous, it would radically reduce the amount of information that would need to be shuttled back and forth in future data processing schemes.
For years, computer architects have been saying that a big new idea in computing was needed. Indeed, as transistors have continued to shrink, rather than continuing to innovate, computer designers have simply adopted a so-called “multicore” approach, where multiple processors are added as more chip real estate became available.
The absence of a major breakthrough was referred to in a remarkable confrontation that took place two years ago during Hot Chips, an annual computer design conference held each summer at Stanford University.
John L. Hennessy, the president of Stanford and a computer design expert, stood before a panel of some of the world’s best computer designers and challenged them to present one fundamentally new idea. He was effectively greeted with silence.
“What is your one big idea?” he asked the panel. “I believe that the next big idea is going to come from someone who is considerably younger than the average age of the people in this room.”
Dr. Ranganathan, who was 36 at the time, was there. He said that he took Dr. Hennessy’s criticism as an inspiration for his work and he believes that nanostore chip design is an example of the kind of big idea that has been missing.
It is not just Dr. Hennessy who has been warning about the end the era of rapidly increasing computer performance. In 2008, Darpa, the Defense Advanced Research Projects Agency assembled a panel of the nation’s best supercomputer experts and asked them to think about ways in which it might be possible to reach an exascale computer — a supercomputer capable of executing one quintillion mathematical calculations in a second, about 1,000 times faster than today’s fastest systems.
The panel, which was led by Peter Kogge, a University of Notre Dame supercomputer designer, came back with pessimistic conclusions. “Will the next decade see the same kind of spectacular progress as the last two did?” he wrote in the January issue of IEEE Spectrum. “Alas, no.” He added: “The party isn’t over, but the police have arrived and the music has been turned way down.”
One reason is computing’s enormous energy appetite. A 10-petaflop supercomputer — scheduled to be built by I.B.M. next year — will consume 15 megawatts of power, roughly the electricity consumed by a city of 15,000 homes. An exascale computer, built with today’s microprocessors, would require 1.6 gigawatts. That would be roughly one and half times the amount of electricity produced by a nuclear power plant.
The panel did, however, support Dr. Ranganathan’s memory-centric approach. It found that the energy cost of a single calculation was about 70 picojoules (a picojoule is one millionth of one millionth of a joule. The energy needed to keep a 100-watt bulb lit for an hour is more than eight million joules). However, when the energy costs of moving the data needed to do a single calculation — moving 200 bits of data in and out of memory multiple times — the real energy cost of a single calculation might be anywhere from 1,000 to 10,000 picojoules.
A range of other technologies are being explored to allow the continued growth of computing power, including ways to build electronic switches smaller than 10 nanometers — thought to be the minimum size for current chip-making techniques.
Last month, for example, researchers at Harvard and Mitre Corporation reported the development of nanoprocessor “tiles” based on electronic switches fabricated from ultrathin germanium-silicon wires.
I.B.M. researchers have been pursuing so-called phase-change memories based on the ability to use an electric current to switch a material from a crystalline to an amorphous state and back again. This technology was commercialized by Samsung last year. More recently, I.B.M. researchers have said that they are excited about the possibility of using carbon nanotubes as an a partial step to build hybrid systems that straddle the nanoelectronic and microelectronic worlds.
Veteran computer designers note that whichever technology wins, the idea of moving computer processing closer to memory has been around for some time, and it may simply be the arrival of nanoscale electronics that finally makes the new architecture possible.
An early effort was called iRAM, in a research project at the University of California, Berkeley, during the late 1990s. Today pressure for memory-oriented computing is coming both from computing challenges posed by smartphones and from the data center, said Christoforos Kozyrakis, a Stanford University computer scientist who worked on the iRAM project in graduate school.
Wednesday, February 23, 2011
Dark Matter and Galaxie Formation
Dark Matter: New Evidence on How Galaxies Are Born
By Michael D. Lemonick Wednesday, Feb. 23, 2011
If you think it's hard to swallow the concept of dark matter, you're not alone. Decades ago, a few astronomers began to suspect that the universe was swarming with some mysterious, invisible substance that was yanking galaxies around with its own powerful gravity. And for those same decades, most of those astronomers' colleagues dismissed the notion as pretty much nuts.
But the evidence kept mounting, and nowadays dark matter is a firmly established concept in modern astrophysics. It pretty much has to exist, in fact, to explain why individual galaxies spin as fast as they do without flying apart, and why groups of galaxies move the way they do in relation to one another. If there weren't 10 times as much dark matter as there are stars and gas clouds and other visible matter, the universe would make no sense. Nature abhors irrationality, and so we live in a universe in which just about every galaxy, including the Milky Way, is held safely inside a huge blob of dark matter like a butterfly floating inside a glass paperweight. (See "The Hubble Space Telescope's Greatest Hits.")
Astrophysicists are also convinced that the dark matter came first, in blobs of various sizes. Those invisible masses then pulled in ordinary matter to make the galaxies. Not all galaxies are created equal, however. Some are pipsqueaks, some are giants and some are true stellar overachievers — so feverishly prolific in their star creation that they churned out up to 1,000 new suns a year for 100 million years. These so-called starburst galaxies have long been a puzzle to astronomers, but a new paper published in Nature may have finally explained them. The answer — once again — is that the dark matter did it.
The creation of a starburst galaxy, says study co-author Asantha Cooray of the University of California, Irvine, is all a matter of blob size. If your blob is too big, hydrogen gas can't fall together efficiently enough to sustain a starmaking frenzy. Instead the gas breaks apart to make several separate, reasonably sedate galaxies. If the dark-matter blob is too small, by contrast, the hydrogen falls together too efficiently. Stars form so quickly and so furiously that their heat keeps the rest of hydrogen from falling in. The frenzy is short-lived. (Watch TIME's video "Herschel: The Telescope for Invisible Stars.")
Cooray and his colleagues figured all of this out with data from the William Herschel Telescope. The Herschel is sensitive to infrared radiation, a type of light originally discovered by the astronomer William Herschel at the turn of the 19th century — which is why the telescope carries his name. Young, far-off, dusty galaxies are especially bright in infrared, and while the Herschel couldn't generate images of individual galaxies, it could measure brighter and dimmer spots in the overall wash of infrared energy streaming in from across the universe. The brighter spots represent denser clots of galaxies; the dimmer spots are sparse regions.
The scientists then compared what they saw with computer simulations of the early universe, which reveal how dark matter should have been distributed. The comparison showed a good match between medium-size lumps of dark matter and starburst galaxies. In other words: the ancient model is consistent with the current reality. "It's not like a new planet, where everyone goes, 'Wow!' " admits Cooray, "but it's a pretty cool result."
Comments on this article by bloggers:
Contrary to the misconception which you perpetuate here, dark matter is not the only option for explaining our observations of galaxies and space. Plasmas are widely accepted to represent 99% of the universe's visible matter. Thus, quite a lot depends upon the accuracy of those models.
Hannes Alfven received the Nobel Physics prize for creating the plasma models around 1970. During his acceptance speech, he warned that he had made mistakes early in his career. Those magnetohydrodynamic models -- the plasma models -- which theorists and astrophysicists to this day rely upon for their computations were in fact "pseudo-pedegagical", meaning that they appeared to help, but in fact were dangerously misleading. He was widely ignored, and we continue to use the same models to this day.
Astrophysicists and cosmologists today claim that galactic rotation curves demand some huge amount of invisible, theoretical matter placed at just the right spot. But, it's worth noting that we also observe magnetic fields to be associated with intergalactic space and the galaxies themselves. This is an incredibly important clue which this space reporter appears to be completely ignoring.
It's important because in the laboratory, magnetic fields and electric currents go hand-in-hand. It's why there is a term "electromagnetic". Where you see one, it is ASSUMED that there exists the other nearby causing it.
But, in space, astrophysicists and cosmologists would prefer to specifically avoid that inference. And yet, plasma is an electrified gas in the laboratory. So, 99% of the matter we see in space with our telescopes is inherently electric. And we can see the magnetic fields to demonstrate it.
By Michael D. Lemonick Wednesday, Feb. 23, 2011
If you think it's hard to swallow the concept of dark matter, you're not alone. Decades ago, a few astronomers began to suspect that the universe was swarming with some mysterious, invisible substance that was yanking galaxies around with its own powerful gravity. And for those same decades, most of those astronomers' colleagues dismissed the notion as pretty much nuts.
But the evidence kept mounting, and nowadays dark matter is a firmly established concept in modern astrophysics. It pretty much has to exist, in fact, to explain why individual galaxies spin as fast as they do without flying apart, and why groups of galaxies move the way they do in relation to one another. If there weren't 10 times as much dark matter as there are stars and gas clouds and other visible matter, the universe would make no sense. Nature abhors irrationality, and so we live in a universe in which just about every galaxy, including the Milky Way, is held safely inside a huge blob of dark matter like a butterfly floating inside a glass paperweight. (See "The Hubble Space Telescope's Greatest Hits.")
Astrophysicists are also convinced that the dark matter came first, in blobs of various sizes. Those invisible masses then pulled in ordinary matter to make the galaxies. Not all galaxies are created equal, however. Some are pipsqueaks, some are giants and some are true stellar overachievers — so feverishly prolific in their star creation that they churned out up to 1,000 new suns a year for 100 million years. These so-called starburst galaxies have long been a puzzle to astronomers, but a new paper published in Nature may have finally explained them. The answer — once again — is that the dark matter did it.
The creation of a starburst galaxy, says study co-author Asantha Cooray of the University of California, Irvine, is all a matter of blob size. If your blob is too big, hydrogen gas can't fall together efficiently enough to sustain a starmaking frenzy. Instead the gas breaks apart to make several separate, reasonably sedate galaxies. If the dark-matter blob is too small, by contrast, the hydrogen falls together too efficiently. Stars form so quickly and so furiously that their heat keeps the rest of hydrogen from falling in. The frenzy is short-lived. (Watch TIME's video "Herschel: The Telescope for Invisible Stars.")
Cooray and his colleagues figured all of this out with data from the William Herschel Telescope. The Herschel is sensitive to infrared radiation, a type of light originally discovered by the astronomer William Herschel at the turn of the 19th century — which is why the telescope carries his name. Young, far-off, dusty galaxies are especially bright in infrared, and while the Herschel couldn't generate images of individual galaxies, it could measure brighter and dimmer spots in the overall wash of infrared energy streaming in from across the universe. The brighter spots represent denser clots of galaxies; the dimmer spots are sparse regions.
The scientists then compared what they saw with computer simulations of the early universe, which reveal how dark matter should have been distributed. The comparison showed a good match between medium-size lumps of dark matter and starburst galaxies. In other words: the ancient model is consistent with the current reality. "It's not like a new planet, where everyone goes, 'Wow!' " admits Cooray, "but it's a pretty cool result."
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Contrary to the misconception which you perpetuate here, dark matter is not the only option for explaining our observations of galaxies and space. Plasmas are widely accepted to represent 99% of the universe's visible matter. Thus, quite a lot depends upon the accuracy of those models.
Hannes Alfven received the Nobel Physics prize for creating the plasma models around 1970. During his acceptance speech, he warned that he had made mistakes early in his career. Those magnetohydrodynamic models -- the plasma models -- which theorists and astrophysicists to this day rely upon for their computations were in fact "pseudo-pedegagical", meaning that they appeared to help, but in fact were dangerously misleading. He was widely ignored, and we continue to use the same models to this day.
Astrophysicists and cosmologists today claim that galactic rotation curves demand some huge amount of invisible, theoretical matter placed at just the right spot. But, it's worth noting that we also observe magnetic fields to be associated with intergalactic space and the galaxies themselves. This is an incredibly important clue which this space reporter appears to be completely ignoring.
It's important because in the laboratory, magnetic fields and electric currents go hand-in-hand. It's why there is a term "electromagnetic". Where you see one, it is ASSUMED that there exists the other nearby causing it.
But, in space, astrophysicists and cosmologists would prefer to specifically avoid that inference. And yet, plasma is an electrified gas in the laboratory. So, 99% of the matter we see in space with our telescopes is inherently electric. And we can see the magnetic fields to demonstrate it.
Monday, February 7, 2011
IceCube - Window on Energy in the Universe
IceCube opens up a window on energy in the universe
AMUNDSEN-SCOTT BASE, ANTARCTICA - The world's newest astronomical observatory is defined by a field of 86 colored flags rippling across an ice-covered polar landscape. Each banner marks a line of glass-covered orbs that stretches down a mile and a half into the ice, like beads on a frozen string.
Known as IceCube, this massive underground array is designed to do what no other observatory has done before - catch a glimpse of elusive neutrinos, ghostly particles that are formed in the hearts of supernovas, black holes and other deep-space objects and may give scientists new information about the origins of the universe.
"The idea with IceCube is to do astronomy, but instead of using light, we're using neutrinos," said Greg Sullivan, a physicist at the University of Maryland who is one of the collaborators on the $279 million project.
"It opens up a window on energy in the universe," he explained. "We've seen particles in outer space that are 10 million times more energetic than the ones we can accelerate on Earth. Neutrinos are a way to try and find out what's causing those very high energy [particles]. It's been a mystery for 100 years."
Astronomers have flocked to the South Pole in the winter for decades, drawn by the sunless skies and atmospheric conditions that make superb star-gazing. A permanent U.S. station has been at the pole since 1956, and several telescopes have been built here to take advantage of the darkness that lasts from late February to early October.
But IceCube is something different, an observatory built entirely beneath the ice. Along each of the 86 cables are strung 60 three-foot spherical detectors, called digital optical modules or DOMs. These glass-covered orbs are designed to find evidence of neutrinos - particles formed in the hearts of stars that are so small they pass right through the Earth (and our bodies) without hitting molecules or other matter.
Since neutrinos have almost no mass and are too small to be seen with a normal telescope, researchers instead are looking for the extremely small and extremely brief flashes of bluish light that are given off when a neutrino's energy trail strikes an oxygen atom in the ice and creates a third particle, called a muon.
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"We thought that if we could . . . detect that light, we could reconstruct the direction and energy of that muon, which would give us the direction of the neutrinos," Sullivan said during a visit last month to the South Pole sponsored by the National Science Foundation.
In the past, scientists have tried to build neutrino detectors in the deep ocean, abandoned mine shafts and the bottom of deep lakes. All the projects failed for different reasons: salt corroded the detectors, for example, or the muon trails were obscured by the natural light given off by plankton.
Astrophysicists have high hopes for the South Pole location. One advantage of the massive icepack is that it provides a "scaffolding . . . infrastructure for the detectors," holding them steady, Jonathan Feng, a particle physicist and cosmologist at the University of California at Irvine, explained in a phone interview. It also presented extreme challenges: Constructing IceCube involved more than 400 technicians and engineers and took seven summers of tough drilling through polar ice.
IceCube's detectors are pointed northward, toward the center of the Earth, so the planet's mass serves as a filter to block most cosmic rays and other particles. Feng noted that in addition to passing through most matter, neutrinos also are not bent by electric and magnetic fields, which can bend other forms of radiation - potentially bringing information more directly from farther corners of the universe.
The National Science Foundation picked up $242 million of Ice Cube's $279 million price tag. The rest was split among science agencies from Germany, Sweden and Belgium, which also cooperated on construction. The University of Wisconsin at Madison, the project's lead institution, coordinated the design, build and software to run it. The university is also coordinating the data distribution, making information available to scientists around the world.
Now that IceCube is up and running, Feng says he's especially interested in what it might reveal about dark matter, mysterious material that scientists postulate makes up five-sixths of the mass of the universe, but which has never been detected directly.
"The entire periodic table is just small fraction of total matter in the universe," Feng said. "The rest is dark matter but it doesn't reflect light or shine light. We don't see it the way we see stars." When dark matter particles inside the sun and other stars collide with each other, neutrinos are created. If IceCube can detect these neutrinos and glean useful data about where they come from, Feng said, "there will be hundreds of scientists jumping up and down to see if it's a signal of dark matter."
Credit for coming up with the idea behind IceCube is generally given to Francis Halzen, a theoretical physicist at the University of Wisconsin. In the late 1980s, Halzen was intrigued by the problem of building a neutrino detector and had studied the failure of other projects. Interviewed at his office in Madison, Halzen said he's forgotten his "eureka" moment back in 1987. "One of my former graduate students says I told him one morning coming out of the elevator," Halzen said. "But I really don't remember. I didn't realize that I would spend most of the rest of my career doing this."
Halzen got together with colleagues at the University of California at Berkeley and began planning a pilot project, called the Antarctic Muon and Neutrino Detector Array, or AMANDA. It began operation at the South Pole in 1993, but only laid a few strings of detectors into the ice.
IceCube, which was conceived in 1999 as a collaboration between U.S. and European agencies, was on a much grander scale. Engineers on the project ran into formidable obstacles. "You can't just buy a drill in Texas and bring it to Antarctica," Halzen said. "We had to figure all these things out."
During the first year summer of drilling in 2004-05, technicians laid only one string of detectors, and Halzen said they nearly gave up. But a University of Wisconsin team developed a special drill that used hot water to drill nearly two miles deep into the ice. Once cooled, the water was pumped back to the surface, reheated and recycled in a closed-loop system. Then the huge hose that carried the water kept breaking under its own weight. "It was a struggle," Halzen said. Finally, one of the engineers found a firm in Venice with the right equipment, "and we eventually made it work."
There were also logistical challenges. Because of limited space at the South Pole station, the IceCube team could deploy no more than 40 workers at a time. Construction crews had to be rotated in by a three-hour flight from the main U.S. facility at McMurdo Station. "It was like solving a crossword puzzle," Halzen said. "Everything and everyone had to fit just perfectly." By the 2008 drilling season, they had put in 20 strings of detectors. The 86th and final string was laid Dec. 19.
IceCube has already found a strange asymmetry to cosmic rays reaching Earth from the southern hemisphere from the direction of a supernova named Vela. "Nobody knows what it means; that's why its interesting," Halzen said.
For all his work in pushing to get IceCube built, Halzen has never been to the South Pole. During the building phase, he said, he was loath to take up valuable space that could have been used for an engineer or construction worker.
"I have had no use to go there, but maybe now," Halzen said. "Last week it was colder here in Madison that at the South Pole."
health-science@washpost.com
AMUNDSEN-SCOTT BASE, ANTARCTICA - The world's newest astronomical observatory is defined by a field of 86 colored flags rippling across an ice-covered polar landscape. Each banner marks a line of glass-covered orbs that stretches down a mile and a half into the ice, like beads on a frozen string.
Known as IceCube, this massive underground array is designed to do what no other observatory has done before - catch a glimpse of elusive neutrinos, ghostly particles that are formed in the hearts of supernovas, black holes and other deep-space objects and may give scientists new information about the origins of the universe.
"The idea with IceCube is to do astronomy, but instead of using light, we're using neutrinos," said Greg Sullivan, a physicist at the University of Maryland who is one of the collaborators on the $279 million project.
"It opens up a window on energy in the universe," he explained. "We've seen particles in outer space that are 10 million times more energetic than the ones we can accelerate on Earth. Neutrinos are a way to try and find out what's causing those very high energy [particles]. It's been a mystery for 100 years."
Astronomers have flocked to the South Pole in the winter for decades, drawn by the sunless skies and atmospheric conditions that make superb star-gazing. A permanent U.S. station has been at the pole since 1956, and several telescopes have been built here to take advantage of the darkness that lasts from late February to early October.
But IceCube is something different, an observatory built entirely beneath the ice. Along each of the 86 cables are strung 60 three-foot spherical detectors, called digital optical modules or DOMs. These glass-covered orbs are designed to find evidence of neutrinos - particles formed in the hearts of stars that are so small they pass right through the Earth (and our bodies) without hitting molecules or other matter.
Since neutrinos have almost no mass and are too small to be seen with a normal telescope, researchers instead are looking for the extremely small and extremely brief flashes of bluish light that are given off when a neutrino's energy trail strikes an oxygen atom in the ice and creates a third particle, called a muon.
ad_icon
"We thought that if we could . . . detect that light, we could reconstruct the direction and energy of that muon, which would give us the direction of the neutrinos," Sullivan said during a visit last month to the South Pole sponsored by the National Science Foundation.
In the past, scientists have tried to build neutrino detectors in the deep ocean, abandoned mine shafts and the bottom of deep lakes. All the projects failed for different reasons: salt corroded the detectors, for example, or the muon trails were obscured by the natural light given off by plankton.
Astrophysicists have high hopes for the South Pole location. One advantage of the massive icepack is that it provides a "scaffolding . . . infrastructure for the detectors," holding them steady, Jonathan Feng, a particle physicist and cosmologist at the University of California at Irvine, explained in a phone interview. It also presented extreme challenges: Constructing IceCube involved more than 400 technicians and engineers and took seven summers of tough drilling through polar ice.
IceCube's detectors are pointed northward, toward the center of the Earth, so the planet's mass serves as a filter to block most cosmic rays and other particles. Feng noted that in addition to passing through most matter, neutrinos also are not bent by electric and magnetic fields, which can bend other forms of radiation - potentially bringing information more directly from farther corners of the universe.
The National Science Foundation picked up $242 million of Ice Cube's $279 million price tag. The rest was split among science agencies from Germany, Sweden and Belgium, which also cooperated on construction. The University of Wisconsin at Madison, the project's lead institution, coordinated the design, build and software to run it. The university is also coordinating the data distribution, making information available to scientists around the world.
Now that IceCube is up and running, Feng says he's especially interested in what it might reveal about dark matter, mysterious material that scientists postulate makes up five-sixths of the mass of the universe, but which has never been detected directly.
"The entire periodic table is just small fraction of total matter in the universe," Feng said. "The rest is dark matter but it doesn't reflect light or shine light. We don't see it the way we see stars." When dark matter particles inside the sun and other stars collide with each other, neutrinos are created. If IceCube can detect these neutrinos and glean useful data about where they come from, Feng said, "there will be hundreds of scientists jumping up and down to see if it's a signal of dark matter."
Credit for coming up with the idea behind IceCube is generally given to Francis Halzen, a theoretical physicist at the University of Wisconsin. In the late 1980s, Halzen was intrigued by the problem of building a neutrino detector and had studied the failure of other projects. Interviewed at his office in Madison, Halzen said he's forgotten his "eureka" moment back in 1987. "One of my former graduate students says I told him one morning coming out of the elevator," Halzen said. "But I really don't remember. I didn't realize that I would spend most of the rest of my career doing this."
Halzen got together with colleagues at the University of California at Berkeley and began planning a pilot project, called the Antarctic Muon and Neutrino Detector Array, or AMANDA. It began operation at the South Pole in 1993, but only laid a few strings of detectors into the ice.
IceCube, which was conceived in 1999 as a collaboration between U.S. and European agencies, was on a much grander scale. Engineers on the project ran into formidable obstacles. "You can't just buy a drill in Texas and bring it to Antarctica," Halzen said. "We had to figure all these things out."
During the first year summer of drilling in 2004-05, technicians laid only one string of detectors, and Halzen said they nearly gave up. But a University of Wisconsin team developed a special drill that used hot water to drill nearly two miles deep into the ice. Once cooled, the water was pumped back to the surface, reheated and recycled in a closed-loop system. Then the huge hose that carried the water kept breaking under its own weight. "It was a struggle," Halzen said. Finally, one of the engineers found a firm in Venice with the right equipment, "and we eventually made it work."
There were also logistical challenges. Because of limited space at the South Pole station, the IceCube team could deploy no more than 40 workers at a time. Construction crews had to be rotated in by a three-hour flight from the main U.S. facility at McMurdo Station. "It was like solving a crossword puzzle," Halzen said. "Everything and everyone had to fit just perfectly." By the 2008 drilling season, they had put in 20 strings of detectors. The 86th and final string was laid Dec. 19.
IceCube has already found a strange asymmetry to cosmic rays reaching Earth from the southern hemisphere from the direction of a supernova named Vela. "Nobody knows what it means; that's why its interesting," Halzen said.
For all his work in pushing to get IceCube built, Halzen has never been to the South Pole. During the building phase, he said, he was loath to take up valuable space that could have been used for an engineer or construction worker.
"I have had no use to go there, but maybe now," Halzen said. "Last week it was colder here in Madison that at the South Pole."
health-science@washpost.com
Wednesday, February 2, 2011
Kepler Finds 1200 Possibilities in New Planets
Kepler Planet Hunter Finds 1,200 Possibilities
By DENNIS OVERBYE
Published: February 2, 2011
New York Times
In a long-awaited announcement, scientists operating NASA’s Kepler planet-hunting satellite reported Wednesday that they had identified 1,235 possible planets orbiting other stars, potentially tripling the number of known planets in the universe.
Of the new candidates, 68 are one-and-a-quarter times the size of the Earth or smaller — smaller, that is, than any previously discovered planets outside the solar system. Fifty-four of the possible exoplanets are in the so-called habitable zones, where temperatures should be moderate enough for liquid water, of stars dimmer and cooler than the Sun; four of these are less than twice the size of Earth, and one is even smaller.
Astronomers said that it would take years to confirm that all these candidates are really planets — by using ground-based telescopes to try to measure their masses, for example — and not just double stars or other strange systems. Many of them might never be vetted because of the dimness of their stars and the lack of telescope time and astronomers to do it all. But statistical tests of a sample of the list suggest that 80 to 95 percent of the objects on it were real, as opposed to blips in the data.
“It boggles the mind,” said William Borucki of the Ames Research Center, Kepler’s leader.
At first glance, none of them appears to be another Earth, the kind of cosmic Eden fit for life as we know it, but the new results represent only four months worth of data on a three-and-a-half-year project, and have left astronomers enthused about the chances they will ultimately reach their goal of finding Earth-like planets in the universe.
“For the first time in human history we have a pool of potentially rocky habitable zone planets,” said Sara Seager of M.I.T., who works with Kepler. “This is the first big step forward to answering the ancient question, ‘How common are other Earths?’ ”
Mr. Borucki noted that since the Kepler telescope surveys only one four-hundredth of the sky, the numbers extrapolated to some 20,000 habitable-zone planets within 3,000 light-years of Earth. He is the lead author of a paper that has been submitted to The Astrophysical Journal describing the new results.
In a separate announcement, to be published in Nature on Thursday, a group of Kepler astronomers led by Jack Lissauer of Ames said they had found a star with six planets — the most Kepler has yet found around one star — orbiting in close ranks in the same plane, no farther from their star than Mercury is from the Sun.
This dense packing, Dr. Lissauer said, seems to violate all the rules astronomers thought they had begun to discern about how planetary systems form and evolve.
“This is sending me back to the drawing board,” he said.
Summarizing the news from the cosmos, Geoffrey W. Marcy of the University of California, Berkeley, a veteran exoplanet hunter and a mainstay of the Kepler work, said, “There are so many messages here that it’s hard to know where to begin.” He called the Borucki team’s announcement “an extraordinary planet windfall, a moment that will be written in textbooks. It will be thought of as watershed.”
Kepler, launched into orbit around the Sun in March 2009, stares at a patch of the Milky Way near the Northern Cross, measuring the brightness of 156,000 stars every 30 minutes, looking for a pattern of dips that would be caused by planets crossing in front of their suns.
The goal is to assess the frequency of Earth-like planets around Sun-like suns in the galaxy. But in the four months of data analyzed so far, a Kepler looking at our own Sun would be lucky to have seen the Earth pass even once. Three transits are required for a planet to show up in Kepler’s elaborate data-processing pipeline, which means that Kepler’s next scheduled data release, in June 2012, could be a moment of truth for the mission.
Habitable planets, in the meantime, could show up at fainter stars than our Sun, where the habitable, or “Goldilocks,” zone, would be smaller and closer to the star and planets in it would rack up transits more quickly.
Attention has been riveted on Wednesday’s data release since June, when Kepler scientists issued their first list, of some 300 stars suspected of harboring planets, but held back another 400 for further study. In the intervening months, Mr. Borucki said, some of those candidates have been eliminated, but hundreds more have been added that would otherwise have been reported in June this year.
One of the sequestered stars was a Sun-like star in the constellation Cygnus that went by the name of KOI 157, for Kepler Object of Interest. It first came to notice in the spring of 2009 when the astronomers saw that it seemed to have five candidate planets, four with nearly the same orbital periods, and in the same plane, like an old vinyl record, Dr. Lissauer recalled. Two of them came so close that every 50 days one of them would look as large as a full moon as seen from the other, Dr. Lissauer calculated.
“I got very interested in this system,” Dr. Lissauer said. “Five was the most we had around any target.” Moreover, the planets’ proximity to one another meant that they would interact gravitationally. In the fall, a sixth planet — the innermost — was found.
By measuring the slight variations in transit times caused by the gravitational interference of the inner five planets with one another, Dr. Lissauer and his colleagues were able to calculate the masses and densities of those planets. These confirmed they were so-called super-Earths, with masses ranging from two to 13 times that of the Earth. But they were also puffy, containing a mixture of rock and gas, rather than being pure rock and iron like another super-Earth, Kepler 10b, a hunk of lava announced last month at a meeting in Seattle.
Dr. Lissauer said, “It suggests that most super-Earths may be more like Neptune than Earth-like.”
Alan Boss, a planetary theorist at the Carnegie Institution of Washington, said the Kepler 11 system, as it is now known, should keep theorists busy and off the streets for a long time. “This system,” he wrote in an e-mail message, “certainly belongs in the pantheon of exoplanet systems: six planets lined up in a plane pointing toward us, waiting patiently for billions of years for humankind to develop sufficient technical capabilities to detect them.”
Mr. Borucki said the growing ubiquity of small planets as revealed by Kepler was a welcome relief from the early days of exoplanet research, when most of the planets discovered were Jupiter-size giants hugging their stars in close orbits, leading theorists to speculate that smaller planets might be thrown away from those environs by gravitational forces or even dragged right into their stars.
“Those little guys are still there,” he said, “and we’re delighted to see them.”
By DENNIS OVERBYE
Published: February 2, 2011
New York Times
In a long-awaited announcement, scientists operating NASA’s Kepler planet-hunting satellite reported Wednesday that they had identified 1,235 possible planets orbiting other stars, potentially tripling the number of known planets in the universe.
Of the new candidates, 68 are one-and-a-quarter times the size of the Earth or smaller — smaller, that is, than any previously discovered planets outside the solar system. Fifty-four of the possible exoplanets are in the so-called habitable zones, where temperatures should be moderate enough for liquid water, of stars dimmer and cooler than the Sun; four of these are less than twice the size of Earth, and one is even smaller.
Astronomers said that it would take years to confirm that all these candidates are really planets — by using ground-based telescopes to try to measure their masses, for example — and not just double stars or other strange systems. Many of them might never be vetted because of the dimness of their stars and the lack of telescope time and astronomers to do it all. But statistical tests of a sample of the list suggest that 80 to 95 percent of the objects on it were real, as opposed to blips in the data.
“It boggles the mind,” said William Borucki of the Ames Research Center, Kepler’s leader.
At first glance, none of them appears to be another Earth, the kind of cosmic Eden fit for life as we know it, but the new results represent only four months worth of data on a three-and-a-half-year project, and have left astronomers enthused about the chances they will ultimately reach their goal of finding Earth-like planets in the universe.
“For the first time in human history we have a pool of potentially rocky habitable zone planets,” said Sara Seager of M.I.T., who works with Kepler. “This is the first big step forward to answering the ancient question, ‘How common are other Earths?’ ”
Mr. Borucki noted that since the Kepler telescope surveys only one four-hundredth of the sky, the numbers extrapolated to some 20,000 habitable-zone planets within 3,000 light-years of Earth. He is the lead author of a paper that has been submitted to The Astrophysical Journal describing the new results.
In a separate announcement, to be published in Nature on Thursday, a group of Kepler astronomers led by Jack Lissauer of Ames said they had found a star with six planets — the most Kepler has yet found around one star — orbiting in close ranks in the same plane, no farther from their star than Mercury is from the Sun.
This dense packing, Dr. Lissauer said, seems to violate all the rules astronomers thought they had begun to discern about how planetary systems form and evolve.
“This is sending me back to the drawing board,” he said.
Summarizing the news from the cosmos, Geoffrey W. Marcy of the University of California, Berkeley, a veteran exoplanet hunter and a mainstay of the Kepler work, said, “There are so many messages here that it’s hard to know where to begin.” He called the Borucki team’s announcement “an extraordinary planet windfall, a moment that will be written in textbooks. It will be thought of as watershed.”
Kepler, launched into orbit around the Sun in March 2009, stares at a patch of the Milky Way near the Northern Cross, measuring the brightness of 156,000 stars every 30 minutes, looking for a pattern of dips that would be caused by planets crossing in front of their suns.
The goal is to assess the frequency of Earth-like planets around Sun-like suns in the galaxy. But in the four months of data analyzed so far, a Kepler looking at our own Sun would be lucky to have seen the Earth pass even once. Three transits are required for a planet to show up in Kepler’s elaborate data-processing pipeline, which means that Kepler’s next scheduled data release, in June 2012, could be a moment of truth for the mission.
Habitable planets, in the meantime, could show up at fainter stars than our Sun, where the habitable, or “Goldilocks,” zone, would be smaller and closer to the star and planets in it would rack up transits more quickly.
Attention has been riveted on Wednesday’s data release since June, when Kepler scientists issued their first list, of some 300 stars suspected of harboring planets, but held back another 400 for further study. In the intervening months, Mr. Borucki said, some of those candidates have been eliminated, but hundreds more have been added that would otherwise have been reported in June this year.
One of the sequestered stars was a Sun-like star in the constellation Cygnus that went by the name of KOI 157, for Kepler Object of Interest. It first came to notice in the spring of 2009 when the astronomers saw that it seemed to have five candidate planets, four with nearly the same orbital periods, and in the same plane, like an old vinyl record, Dr. Lissauer recalled. Two of them came so close that every 50 days one of them would look as large as a full moon as seen from the other, Dr. Lissauer calculated.
“I got very interested in this system,” Dr. Lissauer said. “Five was the most we had around any target.” Moreover, the planets’ proximity to one another meant that they would interact gravitationally. In the fall, a sixth planet — the innermost — was found.
By measuring the slight variations in transit times caused by the gravitational interference of the inner five planets with one another, Dr. Lissauer and his colleagues were able to calculate the masses and densities of those planets. These confirmed they were so-called super-Earths, with masses ranging from two to 13 times that of the Earth. But they were also puffy, containing a mixture of rock and gas, rather than being pure rock and iron like another super-Earth, Kepler 10b, a hunk of lava announced last month at a meeting in Seattle.
Dr. Lissauer said, “It suggests that most super-Earths may be more like Neptune than Earth-like.”
Alan Boss, a planetary theorist at the Carnegie Institution of Washington, said the Kepler 11 system, as it is now known, should keep theorists busy and off the streets for a long time. “This system,” he wrote in an e-mail message, “certainly belongs in the pantheon of exoplanet systems: six planets lined up in a plane pointing toward us, waiting patiently for billions of years for humankind to develop sufficient technical capabilities to detect them.”
Mr. Borucki said the growing ubiquity of small planets as revealed by Kepler was a welcome relief from the early days of exoplanet research, when most of the planets discovered were Jupiter-size giants hugging their stars in close orbits, leading theorists to speculate that smaller planets might be thrown away from those environs by gravitational forces or even dragged right into their stars.
“Those little guys are still there,” he said, “and we’re delighted to see them.”
Monday, January 31, 2011
Kepler Observatory - Life Out There
Life Out There
Gazing Afar for Other Earths, and Other Beings
By DENNIS OVERBYE
Published: January 30, 2011
MOFFETT FIELD, Calif. — In a building at NASA’s Ames Research Center here, computers are sifting and resifting the light from 156,000 stars, seeking to find in the flickering of distant suns the first hints that humanity is not alone in the universe.
Combing 156,000 Stars
Articles in this series will examine the search for Earth-like planets and for new forms of life in the universe.
William Borucki, lead scientist for the Kepler satellite observatory, launched in 2009.
The stars are being monitored by a $600 million satellite observatory named Kepler, whose job is to conduct a kind of Gallup poll of worlds in the cosmos. On Wednesday, Kepler’s astronomers are scheduled to unveil a closely kept list of 400 stars that are their brightest and best bets so far for harboring planets, some of which could turn out to be the smallest and most Earth-like worlds discovered out there to date. They represent the first glimpse of riches to come in a quest that is as old as the imagination and as new as the iPad.
Over the next two or three years, as Kepler continues to stare and sift, astronomers say, it will be able to detect planets in the “Goldilocks” zones, where it is neither too hot nor too cold for liquid water.
“What we want is to find life,” said Geoffrey Marcy, an astronomer at the University of California, Berkeley, who is part of the Kepler team.
William Borucki, 72, the lead scientist, who has spent the last 20 years getting Kepler off the ground, said recently in an interview in his office: “I’ve argued that Kepler is more important than the Hubble Space Telescope. We provide the data mankind needs to move out into space.”
These are science-fiction times. Kepler is only the first step in a process that experts agree will take decades. Both NASA and the European Space Agency have laid plans for a multidecade quest — employing ever more sophisticated and expensive spacecraft — for planets and life beyond Earth.
A roving robot laboratory named Curiosity will depart for Mars on a $2.5 billion mission this fall. Astronomers argue whether the next such mission should go to Jupiter’s moon Europa, with its subsurface ocean; Saturn’s moon Titan, which is coated with a methane slush; or another of Saturn’s moons, Enceladus, which is spouting geysers of water from its interior.
Right now, humans cannot even summon the money or political will to get back to the Moon, let alone set sail for another star. It would take 300,000 years for Voyager 1, now on the way out of the solar system at 39,000 miles per hour, to travel the 20 light-years, or 120 trillion miles, to Gliese 581, one of the nearest planetary systems; Kepler’s planets are from 500 to 3,000 light-years away. NASA and other organizations, like the Planetary Society, have experimented with devices like solar sails, in which a craft is pushed by sunlight or a powerful laser, and ion drives, in which high-energy particles do the propelling.
This is more than just an intellectual exercise, scientists say. Traditional religious images of ourselves as God’s creatures, or even of God, could be in for a rough time if we ever discover pond scum living by completely alien chemical rules on some moon or planet, let alone the Borg — the alien race ruled by a collective mind on “Star Trek” — inhabiting some distant realm.
Moreover, as astronomers keep reminding us, humanity will eventually lose Earth as its home, whether because of global warming or the ultimate plague or a killer asteroid or the Sun’s inevitable demise. Before then, if we want the universe to remember us or even know we were here, we need to get away.
It was only in 1995 that a team of Swiss astronomers led by Michel Mayor of the Geneva Observatory discovered the first planet of another Sun-like star using what is now known as the “wobble” method. A planet gives its star a little gravitational tug as it goes around, causing the star to go back and forth, or wobble, a little as both star and planet circle the same center of gravity. They detected a wobble in the motion of the star 51 Pegasi as an object about half the mass of Jupiter whipped around it every four days.
Like Olives in a Martini Glass
Over the next decade, Dr. Mayor’s group and another planet-hunting team led by Dr. Marcy and R. Paul Butler of the Carnegie Institution leapfrogged each other in finding exoplanets, as they are called. More and more astronomers have joined the hunt, discovering smaller and smaller planets. Astronomers have recorded direct images of four planets swirling like olives in a martini glass around a star known as HR 8799, 130 light-years from Earth in the constellation Pegasus, and another circling Fomalhaut, only 25 light-years from Earth, in the constellation Piscis Austrinus.
There are now more than 500 planets listed on the Jet Propulsion Laboratory’s PlanetQuest Web site. None are habitable.
Among them is the so-called Styrofoam planet — an early trophy of Kepler’s — a planet that is again half as large as Jupiter, but so puffed up by the heat of its star that it is only one-tenth as dense. Another is a planet composed almost entirely of superheated water and sometimes called the Steam World; it is known as Gliese 1214b, about 40 light-years from here in the constellation Ophiuchus.
Last year, a team of American astronomers announced that they had discovered a Goldilocks planet orbiting a dim red dwarf star at just the right distance to harbor water on its surface, making it a potential site for life. Gliese 581g, as it is known, is part of the Gliese 581 system 20 light-years from here, in Libra. But then the Swiss astronomers who first spotted that system were not able to find the Goldilocks planet in their own data, causing many astronomers, but not its discoverers, to doubt that the friendly 581g was real.
The Kepler project grew out of Mr. Borucki’s lifelong love of space.
Mr. Borucki grew up in a small town in Wisconsin, shooting homemade rockets into the sky and praying that they did not hit a neighbor’s cow. “As a kid, this is what you wanted to do,” he said.
After getting a master’s degree in physics from the University of Wisconsin, he went to work on the Apollo Moon program, becoming an expert in precise measurements of light. In 1984, he suggested that such measurements could be used to look for planets.
The idea is that a planet passing in front of its star would block a little of its light — very little. In the case of the Earth, the dip would amount to 84 parts per million in the Sun’s light — less than a hundredth of a percent.
In 1993, when Mr. Borucki and his collaborators proposed building a satellite to do such measurements, NASA said, “If doable, it’s fabulous,” recalled David Koch of the University of Wisconsin, Mr. Borucki’s longtime collaborator. But NASA did not think detectors could be so precise.
NASA rejected their proposal a year later, then again two years after that. “It’s a wonderful thing to have someone tell you over and over again everything that is wrong with your experiment,” Mr. Borucki said. That was the road to improvement.
Peter DaSilva for The New York Times
In 1998, NASA turned the scientists down again, but gave them half a million dollars to spend on lab work. The Kepler mission finally got the nod from NASA in 2001, but with a twist. The Ames Research Center wound up handing over management of the mission, at least until the launching, to the Jet Propulsion Laboratory in Pasadena, Calif., which developed the Vikings and Voyagers. “Here we had been competing against J.P.L. all these years,” Dr. Koch said. “We got over that.” Control has since reverted to Ames.
Kepler was launched from Cape Canaveral into an orbit around the Sun on March 6, 2009. Its gaze is fixed on a patch of sky about 20 full moons across near the Northern Cross, in the constellations Cygnus and Lyra, containing about 4.5 million stars. That is the neighborhood for Kepler’s cosmic census. The job is simply to measure the brightness of 156,000 of those stars every half-hour, looking for the repeated dips caused by planet crossings, or “transits.”
The more times a planet crosses its star, the more easily it is picked up and tagged by computers analyzing Kepler’s data. And Kepler’s first hits were indeed of planets that orbited their suns in a few days in close orbits that would produce oven-cleaner temperatures. The Earth, of course, takes a year to go around the Sun, so it would take two or three years for its analogue orbiting some star in Cygnus to show up in the Kepler data.
“We will find Earth-size planets in habitable zones,” Dr. Marcy stated flatly last month in Seattle.
Required: Absolute Proof
There is a hitch to confirming those planets, however. Such planets would not exert enough of a gravitational tug on their suns to be detectable by the “wobble” method, the main way their masses can be measured. Instead of confirming such planets, Kepler astronomers talk about “validating” them by using high-powered telescopes to make sure, for example, that there is only one star there and not a pair of eclipsing stars or some other phenomenon that could mimic a planet’s shadow.
“Earths are difficult,” Mr. Borucki said. “We’re concerned not to announce anything until we’ve proven six different ways it can’t not be a planet.”
As a result, more and more of Kepler’s future pronouncements will be statistical in nature. Natalie Batalha of San Jose State University, the deputy science team leader for Kepler, said it could be that they will wind up with, say, 100 planets they are 80 percent sure of, which could translate to 80 planets — useful for a census, not so helpful if you’re looking for a place to live.
“It’s a bitter pill to swallow,” said Sara Seager, an M.I.T. planetary astronomer who works with Kepler. “We will be faced with hundreds of planet candidates that may never be fully vetted as planets. We just have to live with statistics.”
But providing statistics, and not pinpointing individual planets, has always been Kepler’s prime mission. The road map to new worlds, Dr. Batalha explained, goes like this: First, Kepler figures out how abundant Earths are and how far you have to go out into the universe to find one. That information is needed to design the next step — a mission that would search the sky for Earth-like planets that are close enough to study. But at 500 to 3,000 light-years away, Kepler’s planets are too far for intense direct scrutiny.
“Once you know where they are, you study the heck out of them,” looking for spectral indications of an atmosphere and anything else, including biomarkers that are the signature of living things, Dr. Batalha wrote in an e-mail. “Everyone and their dog will be looking for biomarkers on these worlds.”
One idea for such a mission is a “starshade” that would float in front of a telescope in space and cancel out the bright light from a star, allowing its much dimmer planets to stand out.
Shading a New Telescope
Indeed, some astronomers have proposed building such a starshade for the James Webb Space Telescope, Hubble’s successor, which is scheduled to be launched by NASA later this decade. “It could potentially not only image an Earth-like planet, but provide some information about its atmosphere and surface,” said David Spergel, an astrophysicist from Princeton.
Mr. Borucki likes to compare the quest for other worlds to the building of the great cathedrals, a task handed from generation to generation of believers. And what if we finally find what we are looking for?
“The fact that we find lots of Earths just means that we have to spend a lot more money to build the next mission and go and find out if they speak English or French,” Mr. Borucki said.
If we are alone, on the other hand, “maybe we’re going to go conquer the whole galaxy,” he said. “Nobody’s out there to stop us.”
Gazing Afar for Other Earths, and Other Beings
By DENNIS OVERBYE
Published: January 30, 2011
MOFFETT FIELD, Calif. — In a building at NASA’s Ames Research Center here, computers are sifting and resifting the light from 156,000 stars, seeking to find in the flickering of distant suns the first hints that humanity is not alone in the universe.
Combing 156,000 Stars
Articles in this series will examine the search for Earth-like planets and for new forms of life in the universe.
William Borucki, lead scientist for the Kepler satellite observatory, launched in 2009.
The stars are being monitored by a $600 million satellite observatory named Kepler, whose job is to conduct a kind of Gallup poll of worlds in the cosmos. On Wednesday, Kepler’s astronomers are scheduled to unveil a closely kept list of 400 stars that are their brightest and best bets so far for harboring planets, some of which could turn out to be the smallest and most Earth-like worlds discovered out there to date. They represent the first glimpse of riches to come in a quest that is as old as the imagination and as new as the iPad.
Over the next two or three years, as Kepler continues to stare and sift, astronomers say, it will be able to detect planets in the “Goldilocks” zones, where it is neither too hot nor too cold for liquid water.
“What we want is to find life,” said Geoffrey Marcy, an astronomer at the University of California, Berkeley, who is part of the Kepler team.
William Borucki, 72, the lead scientist, who has spent the last 20 years getting Kepler off the ground, said recently in an interview in his office: “I’ve argued that Kepler is more important than the Hubble Space Telescope. We provide the data mankind needs to move out into space.”
These are science-fiction times. Kepler is only the first step in a process that experts agree will take decades. Both NASA and the European Space Agency have laid plans for a multidecade quest — employing ever more sophisticated and expensive spacecraft — for planets and life beyond Earth.
A roving robot laboratory named Curiosity will depart for Mars on a $2.5 billion mission this fall. Astronomers argue whether the next such mission should go to Jupiter’s moon Europa, with its subsurface ocean; Saturn’s moon Titan, which is coated with a methane slush; or another of Saturn’s moons, Enceladus, which is spouting geysers of water from its interior.
Right now, humans cannot even summon the money or political will to get back to the Moon, let alone set sail for another star. It would take 300,000 years for Voyager 1, now on the way out of the solar system at 39,000 miles per hour, to travel the 20 light-years, or 120 trillion miles, to Gliese 581, one of the nearest planetary systems; Kepler’s planets are from 500 to 3,000 light-years away. NASA and other organizations, like the Planetary Society, have experimented with devices like solar sails, in which a craft is pushed by sunlight or a powerful laser, and ion drives, in which high-energy particles do the propelling.
This is more than just an intellectual exercise, scientists say. Traditional religious images of ourselves as God’s creatures, or even of God, could be in for a rough time if we ever discover pond scum living by completely alien chemical rules on some moon or planet, let alone the Borg — the alien race ruled by a collective mind on “Star Trek” — inhabiting some distant realm.
Moreover, as astronomers keep reminding us, humanity will eventually lose Earth as its home, whether because of global warming or the ultimate plague or a killer asteroid or the Sun’s inevitable demise. Before then, if we want the universe to remember us or even know we were here, we need to get away.
It was only in 1995 that a team of Swiss astronomers led by Michel Mayor of the Geneva Observatory discovered the first planet of another Sun-like star using what is now known as the “wobble” method. A planet gives its star a little gravitational tug as it goes around, causing the star to go back and forth, or wobble, a little as both star and planet circle the same center of gravity. They detected a wobble in the motion of the star 51 Pegasi as an object about half the mass of Jupiter whipped around it every four days.
Like Olives in a Martini Glass
Over the next decade, Dr. Mayor’s group and another planet-hunting team led by Dr. Marcy and R. Paul Butler of the Carnegie Institution leapfrogged each other in finding exoplanets, as they are called. More and more astronomers have joined the hunt, discovering smaller and smaller planets. Astronomers have recorded direct images of four planets swirling like olives in a martini glass around a star known as HR 8799, 130 light-years from Earth in the constellation Pegasus, and another circling Fomalhaut, only 25 light-years from Earth, in the constellation Piscis Austrinus.
There are now more than 500 planets listed on the Jet Propulsion Laboratory’s PlanetQuest Web site. None are habitable.
Among them is the so-called Styrofoam planet — an early trophy of Kepler’s — a planet that is again half as large as Jupiter, but so puffed up by the heat of its star that it is only one-tenth as dense. Another is a planet composed almost entirely of superheated water and sometimes called the Steam World; it is known as Gliese 1214b, about 40 light-years from here in the constellation Ophiuchus.
Last year, a team of American astronomers announced that they had discovered a Goldilocks planet orbiting a dim red dwarf star at just the right distance to harbor water on its surface, making it a potential site for life. Gliese 581g, as it is known, is part of the Gliese 581 system 20 light-years from here, in Libra. But then the Swiss astronomers who first spotted that system were not able to find the Goldilocks planet in their own data, causing many astronomers, but not its discoverers, to doubt that the friendly 581g was real.
The Kepler project grew out of Mr. Borucki’s lifelong love of space.
Mr. Borucki grew up in a small town in Wisconsin, shooting homemade rockets into the sky and praying that they did not hit a neighbor’s cow. “As a kid, this is what you wanted to do,” he said.
After getting a master’s degree in physics from the University of Wisconsin, he went to work on the Apollo Moon program, becoming an expert in precise measurements of light. In 1984, he suggested that such measurements could be used to look for planets.
The idea is that a planet passing in front of its star would block a little of its light — very little. In the case of the Earth, the dip would amount to 84 parts per million in the Sun’s light — less than a hundredth of a percent.
In 1993, when Mr. Borucki and his collaborators proposed building a satellite to do such measurements, NASA said, “If doable, it’s fabulous,” recalled David Koch of the University of Wisconsin, Mr. Borucki’s longtime collaborator. But NASA did not think detectors could be so precise.
NASA rejected their proposal a year later, then again two years after that. “It’s a wonderful thing to have someone tell you over and over again everything that is wrong with your experiment,” Mr. Borucki said. That was the road to improvement.
Peter DaSilva for The New York Times
In 1998, NASA turned the scientists down again, but gave them half a million dollars to spend on lab work. The Kepler mission finally got the nod from NASA in 2001, but with a twist. The Ames Research Center wound up handing over management of the mission, at least until the launching, to the Jet Propulsion Laboratory in Pasadena, Calif., which developed the Vikings and Voyagers. “Here we had been competing against J.P.L. all these years,” Dr. Koch said. “We got over that.” Control has since reverted to Ames.
Kepler was launched from Cape Canaveral into an orbit around the Sun on March 6, 2009. Its gaze is fixed on a patch of sky about 20 full moons across near the Northern Cross, in the constellations Cygnus and Lyra, containing about 4.5 million stars. That is the neighborhood for Kepler’s cosmic census. The job is simply to measure the brightness of 156,000 of those stars every half-hour, looking for the repeated dips caused by planet crossings, or “transits.”
The more times a planet crosses its star, the more easily it is picked up and tagged by computers analyzing Kepler’s data. And Kepler’s first hits were indeed of planets that orbited their suns in a few days in close orbits that would produce oven-cleaner temperatures. The Earth, of course, takes a year to go around the Sun, so it would take two or three years for its analogue orbiting some star in Cygnus to show up in the Kepler data.
“We will find Earth-size planets in habitable zones,” Dr. Marcy stated flatly last month in Seattle.
Required: Absolute Proof
There is a hitch to confirming those planets, however. Such planets would not exert enough of a gravitational tug on their suns to be detectable by the “wobble” method, the main way their masses can be measured. Instead of confirming such planets, Kepler astronomers talk about “validating” them by using high-powered telescopes to make sure, for example, that there is only one star there and not a pair of eclipsing stars or some other phenomenon that could mimic a planet’s shadow.
“Earths are difficult,” Mr. Borucki said. “We’re concerned not to announce anything until we’ve proven six different ways it can’t not be a planet.”
As a result, more and more of Kepler’s future pronouncements will be statistical in nature. Natalie Batalha of San Jose State University, the deputy science team leader for Kepler, said it could be that they will wind up with, say, 100 planets they are 80 percent sure of, which could translate to 80 planets — useful for a census, not so helpful if you’re looking for a place to live.
“It’s a bitter pill to swallow,” said Sara Seager, an M.I.T. planetary astronomer who works with Kepler. “We will be faced with hundreds of planet candidates that may never be fully vetted as planets. We just have to live with statistics.”
But providing statistics, and not pinpointing individual planets, has always been Kepler’s prime mission. The road map to new worlds, Dr. Batalha explained, goes like this: First, Kepler figures out how abundant Earths are and how far you have to go out into the universe to find one. That information is needed to design the next step — a mission that would search the sky for Earth-like planets that are close enough to study. But at 500 to 3,000 light-years away, Kepler’s planets are too far for intense direct scrutiny.
“Once you know where they are, you study the heck out of them,” looking for spectral indications of an atmosphere and anything else, including biomarkers that are the signature of living things, Dr. Batalha wrote in an e-mail. “Everyone and their dog will be looking for biomarkers on these worlds.”
One idea for such a mission is a “starshade” that would float in front of a telescope in space and cancel out the bright light from a star, allowing its much dimmer planets to stand out.
Shading a New Telescope
Indeed, some astronomers have proposed building such a starshade for the James Webb Space Telescope, Hubble’s successor, which is scheduled to be launched by NASA later this decade. “It could potentially not only image an Earth-like planet, but provide some information about its atmosphere and surface,” said David Spergel, an astrophysicist from Princeton.
Mr. Borucki likes to compare the quest for other worlds to the building of the great cathedrals, a task handed from generation to generation of believers. And what if we finally find what we are looking for?
“The fact that we find lots of Earths just means that we have to spend a lot more money to build the next mission and go and find out if they speak English or French,” Mr. Borucki said.
If we are alone, on the other hand, “maybe we’re going to go conquer the whole galaxy,” he said. “Nobody’s out there to stop us.”
Saturday, December 18, 2010
Babylonia Ahead of Their Time
* Scribes in Old Babylonian period knew Pythagoras's theorem 1,000 years before he did
* Cuneiform tablets in New York exhibition show sophistication of Babylonian mathematicians
* Interest in this strand of history growing
(CNN) -- Over 1,000 years before Pythagoras was calculating the length of a hypotenuse, sophisticated scribes in Mesopotamia were working with the same theory to calculate the area of their farmland.
Working on clay tablets, students would "write" out their math problems in cuneiform script, a method that involved making wedge-shaped impressions in the clay with a blunt reed.
These tablets bear evidence of practical as well as more advanced theoretical math and show just how sophisticated the ancient Babylonians were with numbers -- more than a millennium before Pythagoras and Euclid were doing the same in ancient Greece.
"They are the most sophisticated mathematics from anywhere in the world at that time," said Alexander Jones, a Professor of the History of the Exact Sciences in Antiquity at New York University.
He is co-curator of "Before Pythagoras: The Culture of Old Babylonian Mathematics," an exhibition at the Institute for the Study of the Ancient World in New York.
They are the most sophisticated mathematics from anywhere in the world at that time
--Curator Alexander Jones
"This is nearly 4,000 years ago and there's no other ancient culture at that time that we know of that is doing anything like that level of work. It seems to be going beyond anything that daily life needs," he said.
Many scribes were trained in the ancient city of Nippur in what is now southern Iraq, where a large number of tablets were discovered between the mid-19th century and the 1920s.
Typical problems they worked on involved calculating the area of a given field, or the width of a trench.
These problems, says Jones, required the kind of math training taught to American Grade 10 students, but not in a format we would now recognize.
"It's not like algebra, it's all written out in words and numerals but no symbols and no times signs or equals or anything like that," he said.
This system, and the lack of recognizable Western mathematical symbols such as x and y, meant that it was several years before historians and archaeologists understood just what was represented on these tablets.
It took a young Austrian mathematician in the 1920s, named Otto Neugebauer, to crack the mathematical system and work out what the ancient Babylonians were calculating. But despite his advances, it is only recently that interest in Babylonian math has started to take hold.
"I think that before Neugebauer and even after Neugebauer, there wasn't a lot of attention placed on mathematical training in Babylon even though we have this rich cuneiform history with the tablets," said Jennifer Chi, Associate Director for Exhibitions and Public Programs at Institute for the Study of the Ancient World.
When we think of ancient mathematics, the first names that come to mind are Pythagoras and Euclid. That shouldn't be the case.
One of the aims of the institute, she says, is to find interconnections between ancient cultures as well as look at what the institute sees as under-represented ancient cultures -- and the culture of ancient Babylonian math, she says, is ripe for popular revision.
"When we think of ancient mathematics, the first names that come to mind are Pythagoras and Euclid," she said, but that "this shouldn't be the case."
And though ancient Babylonia is often referred to in popular culture as a "lost" world, in fact much more evidence of mathematical learning from the period exists than from ancient Greece, said Chi.
Jones of New York University believes that there is much more that could be excavated but that, of course, current conditions in Iraq are not favorable. Still, there are enough tablets in collections across the world for mathematical historians to get stuck into.
For non-mathematicians, these tablets are a fascinating document of life in Mesopotamia. Most of the problems displayed are grounded in the everyday needs of ancient Babylonians.
But some tablets show the students engaging in what Jones calls "recreational math" -- math for math's sake.
"The only point of learning to do this kind of thing is really as a mental exercise, as a way of showing how smart you are," he said.
And it seems there is still more to learn from the Babylonians. Duncan Melville is a Professor of Mathematics at St. Lawrence University in Canton, New York, whose special interest is Mesopotamian mathematics.
According to Melville, teachers can continue to learn a thing or two about the way math was taught in Mesopotamia.
"You look at the way they set up their sequences of problems and it's all very carefully graduated, from simple problems to more complicated problems," he said.
"As a teacher of mathematics, it's very interesting to see how they organized their material," he continued. "There's still interesting things to learn from cutting-edge pedagogy 4,000 years ago."
With research continuing into this strand of ancient history, it remains to be seen whether Pythagoras's theorem will come to bear the name of an old Babylonian scribe instead.
From CNN December 18, 2010
* Cuneiform tablets in New York exhibition show sophistication of Babylonian mathematicians
* Interest in this strand of history growing
(CNN) -- Over 1,000 years before Pythagoras was calculating the length of a hypotenuse, sophisticated scribes in Mesopotamia were working with the same theory to calculate the area of their farmland.
Working on clay tablets, students would "write" out their math problems in cuneiform script, a method that involved making wedge-shaped impressions in the clay with a blunt reed.
These tablets bear evidence of practical as well as more advanced theoretical math and show just how sophisticated the ancient Babylonians were with numbers -- more than a millennium before Pythagoras and Euclid were doing the same in ancient Greece.
"They are the most sophisticated mathematics from anywhere in the world at that time," said Alexander Jones, a Professor of the History of the Exact Sciences in Antiquity at New York University.
He is co-curator of "Before Pythagoras: The Culture of Old Babylonian Mathematics," an exhibition at the Institute for the Study of the Ancient World in New York.
They are the most sophisticated mathematics from anywhere in the world at that time
--Curator Alexander Jones
"This is nearly 4,000 years ago and there's no other ancient culture at that time that we know of that is doing anything like that level of work. It seems to be going beyond anything that daily life needs," he said.
Many scribes were trained in the ancient city of Nippur in what is now southern Iraq, where a large number of tablets were discovered between the mid-19th century and the 1920s.
Typical problems they worked on involved calculating the area of a given field, or the width of a trench.
These problems, says Jones, required the kind of math training taught to American Grade 10 students, but not in a format we would now recognize.
"It's not like algebra, it's all written out in words and numerals but no symbols and no times signs or equals or anything like that," he said.
This system, and the lack of recognizable Western mathematical symbols such as x and y, meant that it was several years before historians and archaeologists understood just what was represented on these tablets.
It took a young Austrian mathematician in the 1920s, named Otto Neugebauer, to crack the mathematical system and work out what the ancient Babylonians were calculating. But despite his advances, it is only recently that interest in Babylonian math has started to take hold.
"I think that before Neugebauer and even after Neugebauer, there wasn't a lot of attention placed on mathematical training in Babylon even though we have this rich cuneiform history with the tablets," said Jennifer Chi, Associate Director for Exhibitions and Public Programs at Institute for the Study of the Ancient World.
When we think of ancient mathematics, the first names that come to mind are Pythagoras and Euclid. That shouldn't be the case.
One of the aims of the institute, she says, is to find interconnections between ancient cultures as well as look at what the institute sees as under-represented ancient cultures -- and the culture of ancient Babylonian math, she says, is ripe for popular revision.
"When we think of ancient mathematics, the first names that come to mind are Pythagoras and Euclid," she said, but that "this shouldn't be the case."
And though ancient Babylonia is often referred to in popular culture as a "lost" world, in fact much more evidence of mathematical learning from the period exists than from ancient Greece, said Chi.
Jones of New York University believes that there is much more that could be excavated but that, of course, current conditions in Iraq are not favorable. Still, there are enough tablets in collections across the world for mathematical historians to get stuck into.
For non-mathematicians, these tablets are a fascinating document of life in Mesopotamia. Most of the problems displayed are grounded in the everyday needs of ancient Babylonians.
But some tablets show the students engaging in what Jones calls "recreational math" -- math for math's sake.
"The only point of learning to do this kind of thing is really as a mental exercise, as a way of showing how smart you are," he said.
And it seems there is still more to learn from the Babylonians. Duncan Melville is a Professor of Mathematics at St. Lawrence University in Canton, New York, whose special interest is Mesopotamian mathematics.
According to Melville, teachers can continue to learn a thing or two about the way math was taught in Mesopotamia.
"You look at the way they set up their sequences of problems and it's all very carefully graduated, from simple problems to more complicated problems," he said.
"As a teacher of mathematics, it's very interesting to see how they organized their material," he continued. "There's still interesting things to learn from cutting-edge pedagogy 4,000 years ago."
With research continuing into this strand of ancient history, it remains to be seen whether Pythagoras's theorem will come to bear the name of an old Babylonian scribe instead.
From CNN December 18, 2010
Thursday, December 16, 2010
Electromagnetic Energy Naval Rail Gun
(Dec. 14) -- The world's most powerful gun is one step closer to becoming the super-weapon of the future.
The Navy on Friday demonstrated a record-setting 33-megajoule shot from its developmental electromagnetic rail gun, a weapon that will be able to shoot farther than conventional guns. This weapon of the future could someday go on U.S. Navy ships, but for right now, it's a science and technology project.
Normally, a ship-based weapon would require gunpowder or a rocket boost to shoot projectiles, but the electromagnetic gun is powered by an electric pulse generated by the ship. Since the projectiles travel at speeds of more than seven times the speed of sound, they don't even require high explosives to pack a big punch: The kinetic energy of the projectile is more than enough to create a lethal effect.
Why does the Navy want it? Range and speed make the rail gun a particularly attractive weapon for the Navy, though other advantages include its accuracy and safety onboard a ship (because it doesn't require high explosives). "The 33-megajoule shot means the Navy can fire projectiles at least 110 nautical miles (126 miles), placing sailors and Marines at a safe standoff distance and out of harm's way, and the high velocities achievable are tactically relevant for air and missile defense," Rear Adm. Nevin Carr, chief of naval research, said in a release announcing the latest test.
How much does it cost? The Navy has budgeted about $250 million for the development of the prototype rail gun. It's impossible to say how much the final system would cost to buy. As with any new weapon system, the price tag is likely to be high, but advocates for the rail gun point out the projectiles would be cheaper than conventional missiles and ammunition.
When will the weapon be used on a ship? Not anytime soon. The Navy projects it won't be ready until sometime in the 2020 to 2025 time range, and that assumes the Navy pursues it beyond the prototype.
Filed under: Nation, Tech, AOL Original
The Navy on Friday demonstrated a record-setting 33-megajoule shot from its developmental electromagnetic rail gun, a weapon that will be able to shoot farther than conventional guns. This weapon of the future could someday go on U.S. Navy ships, but for right now, it's a science and technology project.
Normally, a ship-based weapon would require gunpowder or a rocket boost to shoot projectiles, but the electromagnetic gun is powered by an electric pulse generated by the ship. Since the projectiles travel at speeds of more than seven times the speed of sound, they don't even require high explosives to pack a big punch: The kinetic energy of the projectile is more than enough to create a lethal effect.
Why does the Navy want it? Range and speed make the rail gun a particularly attractive weapon for the Navy, though other advantages include its accuracy and safety onboard a ship (because it doesn't require high explosives). "The 33-megajoule shot means the Navy can fire projectiles at least 110 nautical miles (126 miles), placing sailors and Marines at a safe standoff distance and out of harm's way, and the high velocities achievable are tactically relevant for air and missile defense," Rear Adm. Nevin Carr, chief of naval research, said in a release announcing the latest test.
How much does it cost? The Navy has budgeted about $250 million for the development of the prototype rail gun. It's impossible to say how much the final system would cost to buy. As with any new weapon system, the price tag is likely to be high, but advocates for the rail gun point out the projectiles would be cheaper than conventional missiles and ammunition.
When will the weapon be used on a ship? Not anytime soon. The Navy projects it won't be ready until sometime in the 2020 to 2025 time range, and that assumes the Navy pursues it beyond the prototype.
Filed under: Nation, Tech, AOL Original
Sunday, December 5, 2010
New Life Form - Is God Dead?
AOL News Article, Dec. 5, 2010
Does a New Life Form Mean God Is Dead?
David Gibson
Religion Reporter
The discovery of what is apparently an entirely new form of life -- a bacteria based on toxic arsenic rather than phosphorus, one of the six building blocks of all life on Earth -- has set the scientific world abuzz, prompting White House inquiries to NASA and threatening to upend longstanding beliefs about biology.
But some say the announcement also signals an end to religious faith, or at least the beginning of the end, because it implies that life can spring forth unexpectedly on Earth or even on other planets, and in unexpected forms -- developments that seem to run counter to literal readings of biblical creation accounts.
"The polite thing to say is that discoveries such as this don't really impeach the credibility of established religion, but in truth of course they really do," David Niose, president of the American Humanist Association (AHA), a leading secularist organization, said of this week's revelations about the microbes discovered in Lake Mono in California.
"The fact that life can spring forth in this way from nature, taken in context with what else we've learned in recent centuries about space and time, surely makes it less plausible that the human animal is the specially favored creation of all-powerful, all-knowing divinity," Niose said.
Another shot in the Wars of Science and Religion? Maybe not.
The arsenic-based microbe discovery "sounds like a nice piece of work; we'll see where it goes from here," Brother Guy Consolmagno, a Jesuit and a planetary scientist at the Vatican Observatory, wrote in an e-mail to Politics Daily. (Yes, the Catholic Church was doing science long before Galileo.)
"But," he added, "any scientific discovery that broadens our knowledge of creation, deepens our understanding of the Creator."
Consolmagno, who a few weeks ago made news for saying he'd be delighted to find intelligent life on other planets, is typical of religious believers who don't see faith and science as natural enemies.
Even some vocal atheists who see belief and science as inevitable opponents -- with belief the problem, not the solution -- weren't buying the AHA's arguments about the discovery's importance.
"I regret to say that the American Humanists got the story wrong," PZ Myers, a biologist at the University of Minnesota and a famously trenchant critic of religion, told Politics Daily. Myers, who details his arguments at his blog, says the problem is their reading of the science.
"They say 'a new form of life has been discovered that apparently evolved outside the scope of all previously discovered life on Earth,' and this is not correct: the bacteria studied share a common ancestor with us, and the novelty of the discovery was not the organism, but that this entirely earthly organism was capable of incorporating arsenic into its chemistry. So no, their claims of its significant impact on our understanding of the history of life on Earth are overblown."
Myers does see a silver lining of sorts (at least from his non-believer's point of view) because the discovery "does represent an incremental increase in our understanding, just as science does every day."
"The point should be that the whole of science provides a direct challenge to religious belief, not that any one event is so definitive," Myers said.
Brother Guy would disagree with that assertion, but he pointed out that for the AHA and similar groups, "obviously this is no 'proof' since obviously they'd decided years ago, for whatever other reasons, that there was no God."
Faith, it seems, comes in many forms.
Niose of the American Humanist Association did concede that it is "unlikely that this discovery will change the minds of those who insist on a literal interpretation of the Bible."
"To them, the world is about 6,000 years old and evolution is a hoax, and no amount of scientific evidence will change that. For the rest of us, however, this discovery is indeed profound, and it adds to the mountains of evidence that already point to the humanistic lifestance as being our best hope."
Maybe the true test of the impact of the discovery will come in a few years time, when we can see whether there are more tourists visiting Lake Mono looking for the arsenic-eating bugs or more pilgrims checking out the full-scale replica of Noah's Ark that a well-known creationist group said this week it will build in northern Kentucky -- at a cost of $150 million, including taxpayer subsidies.
Given the success of the group's Creation Museum, which drew its millionth visitor last spring, it'd be wise not to bet against the Ark.
David Gibson »
Does a New Life Form Mean God Is Dead?
David Gibson
Religion Reporter
The discovery of what is apparently an entirely new form of life -- a bacteria based on toxic arsenic rather than phosphorus, one of the six building blocks of all life on Earth -- has set the scientific world abuzz, prompting White House inquiries to NASA and threatening to upend longstanding beliefs about biology.
But some say the announcement also signals an end to religious faith, or at least the beginning of the end, because it implies that life can spring forth unexpectedly on Earth or even on other planets, and in unexpected forms -- developments that seem to run counter to literal readings of biblical creation accounts.
"The polite thing to say is that discoveries such as this don't really impeach the credibility of established religion, but in truth of course they really do," David Niose, president of the American Humanist Association (AHA), a leading secularist organization, said of this week's revelations about the microbes discovered in Lake Mono in California.
"The fact that life can spring forth in this way from nature, taken in context with what else we've learned in recent centuries about space and time, surely makes it less plausible that the human animal is the specially favored creation of all-powerful, all-knowing divinity," Niose said.
Another shot in the Wars of Science and Religion? Maybe not.
The arsenic-based microbe discovery "sounds like a nice piece of work; we'll see where it goes from here," Brother Guy Consolmagno, a Jesuit and a planetary scientist at the Vatican Observatory, wrote in an e-mail to Politics Daily. (Yes, the Catholic Church was doing science long before Galileo.)
"But," he added, "any scientific discovery that broadens our knowledge of creation, deepens our understanding of the Creator."
Consolmagno, who a few weeks ago made news for saying he'd be delighted to find intelligent life on other planets, is typical of religious believers who don't see faith and science as natural enemies.
Even some vocal atheists who see belief and science as inevitable opponents -- with belief the problem, not the solution -- weren't buying the AHA's arguments about the discovery's importance.
"I regret to say that the American Humanists got the story wrong," PZ Myers, a biologist at the University of Minnesota and a famously trenchant critic of religion, told Politics Daily. Myers, who details his arguments at his blog, says the problem is their reading of the science.
"They say 'a new form of life has been discovered that apparently evolved outside the scope of all previously discovered life on Earth,' and this is not correct: the bacteria studied share a common ancestor with us, and the novelty of the discovery was not the organism, but that this entirely earthly organism was capable of incorporating arsenic into its chemistry. So no, their claims of its significant impact on our understanding of the history of life on Earth are overblown."
Myers does see a silver lining of sorts (at least from his non-believer's point of view) because the discovery "does represent an incremental increase in our understanding, just as science does every day."
"The point should be that the whole of science provides a direct challenge to religious belief, not that any one event is so definitive," Myers said.
Brother Guy would disagree with that assertion, but he pointed out that for the AHA and similar groups, "obviously this is no 'proof' since obviously they'd decided years ago, for whatever other reasons, that there was no God."
Faith, it seems, comes in many forms.
Niose of the American Humanist Association did concede that it is "unlikely that this discovery will change the minds of those who insist on a literal interpretation of the Bible."
"To them, the world is about 6,000 years old and evolution is a hoax, and no amount of scientific evidence will change that. For the rest of us, however, this discovery is indeed profound, and it adds to the mountains of evidence that already point to the humanistic lifestance as being our best hope."
Maybe the true test of the impact of the discovery will come in a few years time, when we can see whether there are more tourists visiting Lake Mono looking for the arsenic-eating bugs or more pilgrims checking out the full-scale replica of Noah's Ark that a well-known creationist group said this week it will build in northern Kentucky -- at a cost of $150 million, including taxpayer subsidies.
Given the success of the group's Creation Museum, which drew its millionth visitor last spring, it'd be wise not to bet against the Ark.
David Gibson »
Thursday, October 28, 2010
Scientists - Tens of Billions of Earth Size Planets in Milky Way
Scientists estimate tens of billions of Earth-size planets in Milky Way
Gallery
Searching for Earth-size planets outside our solar system
According to scientists, there are tens of billions of Earth-size planets in the galaxy.
By Marc Kaufman
Washington Post Staff Writer
Thursday, October 28, 2010; 2:02 PM
Nobody has seen them yet, but scientists now believe there are tens of billions of planets the general size and bulk of Earth in the Milky Way galaxy alone - a startling conclusion based on four years of viewing a small section of the nighttime sky.
Scientists estimate tens of billions of Earth-size planets in Milky Way
The estimate, made by astronomers Andrew Howard and Geoffrey Marcy of the University of California at Berkeley, flows from the simple logic that the number of small but detectable exoplanets - planets outside Earth's solar system - is substantially larger than the number of big exoplanets in distant solar systems.
In a paper released Thursday by the journal Science, the two report that based on this galactic preference for smaller planets, they can predict that almost one quarter of the stars similar to our sun will have Earth-size planets orbiting them.
"This is the first estimate based on actual measurements of the fraction of stars that have Earth-size planets," said Marcy, who did his observing with Howard at the Keck Observatory in Hawaii.
Their observations and extrapolations say nothing about whether all these Earth-size planets will actually have the characteristics of Earth: its density, its just-right distance from the sun, the fact that it is a rocky structure rather than gaseous ball.
But Marcy said that with so many Earth-size planets now expected to be orbiting distant suns - something on the order of 50,000,000,000,000,000,000,000 across the universe - the likelihood is high that many are in "habitable zones" where life can theoretically exist.
"It's tantalizing, without a doubt, to think some of those Earths are in habitable zones," Marcy said. "And based on what we know, really, why wouldn't they be?"
Current planet-hunting technology allows astronomers to find exoplanets down to the size of so-called super-Earths that are three times the size of our planet. The new conclusion that billions of planets similar in mass (or bulk) to Earth exist in the Milky Way is based on extrapolations of the number of these super-Earths compared with the number of larger exoplanets. Because the finding is not based on firm measurements, Marcy said "it's a very exciting set of numbers that we have confidence in, but there are yellow flags."
ad_icon
Exoplanet hunters, who found the first planet outside our solar system in 1995, are entering a period of especially heightened and excited discovery. The new assessment from Howard and Marcy, funded by NASA and Keck Observatory, comes only weeks after two other astronomers published a paper saying they had detected an apparently rocky planet in a habitable zone around a star relatively close to Earth called Gliese 581G.
That conclusion by Steven Vogt of the University of California at Santa Cruz and Paul Butler of the Carnegie Institution in Washington, has not been confirmed, and some have challenged the discovery, especially a Swiss team that has been a leader in exoplanet research. But very few now doubt that Earth-size and Earth-like exoplanets in habitable zones will be found in the months and years ahead.
The assessment that Earth-size planets are ubiquitous in distant solar systems is expected to get additional support in February when the scientists operating NASA's Kepler Mission, which is searching for Earth-size and habitable planets, report on what they have been finding.
In a previous paper, the Kepler team reported finding about 350 new candidate planets that they are now in the process of confirming. Since the first exoplanet was identified 15 years ago, some 500 more both large and small have been discovered and confirmed.
Most were detected by measuring the minute wobbles of stars caused by the gravitational pull of the exoplanets that orbit them. This technique has been dramatically refined in recent years, and astronomers have been given the long telescope observation times needed to make the necessary measurements. The best planet hunters can now detect solar wobbles of as little as one meter per second.
The field has also been revolutionized by other increasingly sophisticated methods of detecting exoplanets, most especially using the "transit" method that looks for tiny reductions in the light coming from target stars - usually on the order of 100 parts per million. If these one-to-16-hour reductions are observed in a regular pattern over time, then astronomers know a planet is orbiting its sun.
Kepler mission is using similar "transiting" to search for Earth-size planets in one small section of the sky. Marcy, who is a member of the Kepler science team, said the orbiting telescope will survey thousands of stars to determine with unprecedented precision how many are circled by exoplanets, and especially by Earth-size exoplanets that might be in habitable zones. The size of the exoplanet can be determined by the amount the brightness of the star decreases when it transits its sun.
"This is an extraordinarily exciting time in exoplanets and distant Earths," Marcy said. "Think of it: We know that Aristotle was once at a cafe outside Athens drinking ouzo and speculating about whether there are other Earths in the universe. That's a question we're getting much closer to answering."
The 166 solar systems reported on Thursday by Howard and Marcy are all within 80 light-years of Earth - a short distance by astronomical measures. "What this means is that, as NASA develops new techniques over the next decade to find truly Earth-size planets, it won't have to look too far," Howard said.
Of 100 typical sun-like stars, his team determined, astronomers can expect to find two the size of Jupiter, six the size of Neptune and twelve "super-Earths" between three and ten times the size of our planet. This progression led to the conclusion that 100 sun-like stars would be orbited by 23 planets sized between one-half of an Earth and two Earths.
Gallery
Searching for Earth-size planets outside our solar system
According to scientists, there are tens of billions of Earth-size planets in the galaxy.
By Marc Kaufman
Washington Post Staff Writer
Thursday, October 28, 2010; 2:02 PM
Nobody has seen them yet, but scientists now believe there are tens of billions of planets the general size and bulk of Earth in the Milky Way galaxy alone - a startling conclusion based on four years of viewing a small section of the nighttime sky.
Scientists estimate tens of billions of Earth-size planets in Milky Way
The estimate, made by astronomers Andrew Howard and Geoffrey Marcy of the University of California at Berkeley, flows from the simple logic that the number of small but detectable exoplanets - planets outside Earth's solar system - is substantially larger than the number of big exoplanets in distant solar systems.
In a paper released Thursday by the journal Science, the two report that based on this galactic preference for smaller planets, they can predict that almost one quarter of the stars similar to our sun will have Earth-size planets orbiting them.
"This is the first estimate based on actual measurements of the fraction of stars that have Earth-size planets," said Marcy, who did his observing with Howard at the Keck Observatory in Hawaii.
Their observations and extrapolations say nothing about whether all these Earth-size planets will actually have the characteristics of Earth: its density, its just-right distance from the sun, the fact that it is a rocky structure rather than gaseous ball.
But Marcy said that with so many Earth-size planets now expected to be orbiting distant suns - something on the order of 50,000,000,000,000,000,000,000 across the universe - the likelihood is high that many are in "habitable zones" where life can theoretically exist.
"It's tantalizing, without a doubt, to think some of those Earths are in habitable zones," Marcy said. "And based on what we know, really, why wouldn't they be?"
Current planet-hunting technology allows astronomers to find exoplanets down to the size of so-called super-Earths that are three times the size of our planet. The new conclusion that billions of planets similar in mass (or bulk) to Earth exist in the Milky Way is based on extrapolations of the number of these super-Earths compared with the number of larger exoplanets. Because the finding is not based on firm measurements, Marcy said "it's a very exciting set of numbers that we have confidence in, but there are yellow flags."
ad_icon
Exoplanet hunters, who found the first planet outside our solar system in 1995, are entering a period of especially heightened and excited discovery. The new assessment from Howard and Marcy, funded by NASA and Keck Observatory, comes only weeks after two other astronomers published a paper saying they had detected an apparently rocky planet in a habitable zone around a star relatively close to Earth called Gliese 581G.
That conclusion by Steven Vogt of the University of California at Santa Cruz and Paul Butler of the Carnegie Institution in Washington, has not been confirmed, and some have challenged the discovery, especially a Swiss team that has been a leader in exoplanet research. But very few now doubt that Earth-size and Earth-like exoplanets in habitable zones will be found in the months and years ahead.
The assessment that Earth-size planets are ubiquitous in distant solar systems is expected to get additional support in February when the scientists operating NASA's Kepler Mission, which is searching for Earth-size and habitable planets, report on what they have been finding.
In a previous paper, the Kepler team reported finding about 350 new candidate planets that they are now in the process of confirming. Since the first exoplanet was identified 15 years ago, some 500 more both large and small have been discovered and confirmed.
Most were detected by measuring the minute wobbles of stars caused by the gravitational pull of the exoplanets that orbit them. This technique has been dramatically refined in recent years, and astronomers have been given the long telescope observation times needed to make the necessary measurements. The best planet hunters can now detect solar wobbles of as little as one meter per second.
The field has also been revolutionized by other increasingly sophisticated methods of detecting exoplanets, most especially using the "transit" method that looks for tiny reductions in the light coming from target stars - usually on the order of 100 parts per million. If these one-to-16-hour reductions are observed in a regular pattern over time, then astronomers know a planet is orbiting its sun.
Kepler mission is using similar "transiting" to search for Earth-size planets in one small section of the sky. Marcy, who is a member of the Kepler science team, said the orbiting telescope will survey thousands of stars to determine with unprecedented precision how many are circled by exoplanets, and especially by Earth-size exoplanets that might be in habitable zones. The size of the exoplanet can be determined by the amount the brightness of the star decreases when it transits its sun.
"This is an extraordinarily exciting time in exoplanets and distant Earths," Marcy said. "Think of it: We know that Aristotle was once at a cafe outside Athens drinking ouzo and speculating about whether there are other Earths in the universe. That's a question we're getting much closer to answering."
The 166 solar systems reported on Thursday by Howard and Marcy are all within 80 light-years of Earth - a short distance by astronomical measures. "What this means is that, as NASA develops new techniques over the next decade to find truly Earth-size planets, it won't have to look too far," Howard said.
Of 100 typical sun-like stars, his team determined, astronomers can expect to find two the size of Jupiter, six the size of Neptune and twelve "super-Earths" between three and ten times the size of our planet. This progression led to the conclusion that 100 sun-like stars would be orbited by 23 planets sized between one-half of an Earth and two Earths.
Thursday, September 30, 2010
Stem Cells From Skin - Same As Embryonic
Scientists overcome hurdles to stem cell alternatives
By Rob Stein
Washington Post Staff Writer
Thursday, September 30, 2010; 8:43 PM
Scientists have invented an efficient way to produce apparently safe alternatives to human embryonic stem cells without destroying embryos, a long-sought step toward bypassing the moral morass surrounding one of the most promising fields in medicine.
A team of researchers at the Harvard Stem Cell Institute in Boston published a series of experiments Thursday showing that synthetic biological signals can quickly reprogram ordinary skin cells into entities that appear virtually identical to embryonic stem cells. Moreover, the same strategy can then turn those cells into ones that could be used for transplants.
"This is going to be very exciting to the research community," said Derrick J. Rossi of the Children's Hospital Boston, who led the research published in the journal Cell Stem Cell. "We now have an experimental paradigm for generating patient-specific cells highly efficiently and safely and also taking those cells to clinically useful cell types."
Scientists hope stem cells will lead to cures for diabetes, Alzheimer's disease, spinal cord injuries, heart attacks and many other ailments because they can turn into almost any tissue in the body, potentially providing an invaluable source of cells to replace those damaged by disease or injury. But the cells can only be obtained by destroying days-old embryos.
The cells produced by the Harvard team, known as induced pluripotent stem cells or iPS cells, would avoid that ethical objection and could in some ways be superior to embryonic stem cells. For example, iPS cells could enable scientists to take an easily obtainable skin cell from any patient and use it to create perfectly matched cells, tissue and potentially even entire organs for transplants that would be immune to rejection.
'Game changer'
While cautioning that the work needed to be repeated elsewhere and explored further, other researchers said the technique appeared to represent a major development in the promising field of "regenerative medicine," which aims to create treatments tailored to individual patients.
"All I can say is 'wow' - this is a game changer," said Robert Lanza, a stem cell researcher at Advanced Cell Technology in Worcester, Mass. "It would solve some of the most important problems in the field." The results were so striking that the Harvard Stem Cell Institute where Rossi works had already ordered every scientist working on iPS cells to switch to the new process.
"This paper is a major paper, in my view, in the field of regenerative medicine," said Douglas A. Melton, a leading stem cell researcher who co-directs the institute.
The announcement comes as the future of federal funding for embryonic stem cell research hangs in doubt. A federal judge stunned the field Aug. 23 by ruling that the Obama administration's more permissive policy for funding the research violated a federal law barring taxpayer dollars from being used for studies that involve destroying human embryos. An appeals court Tuesday let the funding continue until the case is resolved.
Opponents of human embryonic stem cell research seized on the development as the most convincing evidence yet that the morally questionable cells were unnecessary.
"With each new study it becomes more and more implausible to claim that scientists must rely on destruction of human embryos to achieve rapid progress in regenerative medicine," said Richard M. Doerflinger of the U.S. Conference of Catholic Bishops.
Rossi and other researchers, however, said that embryonic stem cells were still crucial because, among other things, they remained irreplaceable for evaluating alternatives.
"The new report provides a substantial advance," said National Institutes of Health Director Francis S. Collins. "But this research in no way reduces the importance of comparing the resulting iPS cells to human embryonic stem cells. Previous research has shown that iPS cells retain some memory of their tissue of origin, which may have important implications for their use in therapeutics. To explore these important potential differences, iPS research must continue to be conducted side by side with human embryonic cell research."
In 2006, researchers discovered that they could coax adult cells into a state that appeared identical to embryonic stem cells and then, just like embryonic stem cells, morph these iPS cells into various tissue. But the process involved inserting genes into cells using retroviruses, which raised the risk the cells could cause cancer. Since then, scientists have been trying to develop safer methods. Several approaches using chemicals or other types of viruses have shown promise. But none has eliminated the safety concerns, and most have been slow and balky.
Cell conversion
The new approach involves molecules known as "messenger RNA" (mRNA), which cells use to create proteins they need carry out vital functions. Working in the laboratory, the researchers created mRNA molecules carrying the instructions for the cell's machinery to produce the four key proteins needed to reprogram into iPS cells.
After tinkering with the mRNA molecules to make signals that the cells would not destroy as dangerous invaders, the researchers found that a daily cocktail of their creations was remarkably fast and efficient at reprogramming the cells. The technique converted the cells in about half the time of previous methods--only about 17 days--with surprising economy--up to 100 times more efficient that the standard approach. "We ended up with so many colonies of cells all over the place that we had to stop the experiment," Rossi said.
Moreover, the cells had not experienced any disturbing changes in their DNA caused by previous methods and appeared much more indistinguishable from embryonic stem cells than iPS cells created using other methods. In addition, the researchers went one step further and showed that they could use the strategy to quickly and easily convert the iPS cells they created into a specific cell types - in this case muscle cells.
"If you put all these things together, several of the major hurdles towards clinical translation of iPS cells are addressed by this technology," Rossi said. "That's what we've very excited about." Others agreed. Lanza, for example, called the approach "almost too good to be true," saying it evoked the magical alchemy of "turning lead into gold." "The ability to safely and efficiently generate patient-specific cells has the potential to transform transplantation medicine," Lanza said.
In an e-mail, stem cell pioneer Shinya Yamanaka of Kyoto University in Japan, who helped discover iPS cells, said he planned to immediately try the technique in his lab. "The standard method to generate [iPS cells] for clinical applications has yet to be established," Yamanaka wrote. "I think this method has the potential for it."
Rossi said the approach should also be useful far beyond stem cells by offering a way to treat any genetic condition in which a protein is missing, deficient or defective.
"It has amazing potential in the therapeutic realm," Rossi said.
By Rob Stein
Washington Post Staff Writer
Thursday, September 30, 2010; 8:43 PM
Scientists have invented an efficient way to produce apparently safe alternatives to human embryonic stem cells without destroying embryos, a long-sought step toward bypassing the moral morass surrounding one of the most promising fields in medicine.
A team of researchers at the Harvard Stem Cell Institute in Boston published a series of experiments Thursday showing that synthetic biological signals can quickly reprogram ordinary skin cells into entities that appear virtually identical to embryonic stem cells. Moreover, the same strategy can then turn those cells into ones that could be used for transplants.
"This is going to be very exciting to the research community," said Derrick J. Rossi of the Children's Hospital Boston, who led the research published in the journal Cell Stem Cell. "We now have an experimental paradigm for generating patient-specific cells highly efficiently and safely and also taking those cells to clinically useful cell types."
Scientists hope stem cells will lead to cures for diabetes, Alzheimer's disease, spinal cord injuries, heart attacks and many other ailments because they can turn into almost any tissue in the body, potentially providing an invaluable source of cells to replace those damaged by disease or injury. But the cells can only be obtained by destroying days-old embryos.
The cells produced by the Harvard team, known as induced pluripotent stem cells or iPS cells, would avoid that ethical objection and could in some ways be superior to embryonic stem cells. For example, iPS cells could enable scientists to take an easily obtainable skin cell from any patient and use it to create perfectly matched cells, tissue and potentially even entire organs for transplants that would be immune to rejection.
'Game changer'
While cautioning that the work needed to be repeated elsewhere and explored further, other researchers said the technique appeared to represent a major development in the promising field of "regenerative medicine," which aims to create treatments tailored to individual patients.
"All I can say is 'wow' - this is a game changer," said Robert Lanza, a stem cell researcher at Advanced Cell Technology in Worcester, Mass. "It would solve some of the most important problems in the field." The results were so striking that the Harvard Stem Cell Institute where Rossi works had already ordered every scientist working on iPS cells to switch to the new process.
"This paper is a major paper, in my view, in the field of regenerative medicine," said Douglas A. Melton, a leading stem cell researcher who co-directs the institute.
The announcement comes as the future of federal funding for embryonic stem cell research hangs in doubt. A federal judge stunned the field Aug. 23 by ruling that the Obama administration's more permissive policy for funding the research violated a federal law barring taxpayer dollars from being used for studies that involve destroying human embryos. An appeals court Tuesday let the funding continue until the case is resolved.
Opponents of human embryonic stem cell research seized on the development as the most convincing evidence yet that the morally questionable cells were unnecessary.
"With each new study it becomes more and more implausible to claim that scientists must rely on destruction of human embryos to achieve rapid progress in regenerative medicine," said Richard M. Doerflinger of the U.S. Conference of Catholic Bishops.
Rossi and other researchers, however, said that embryonic stem cells were still crucial because, among other things, they remained irreplaceable for evaluating alternatives.
"The new report provides a substantial advance," said National Institutes of Health Director Francis S. Collins. "But this research in no way reduces the importance of comparing the resulting iPS cells to human embryonic stem cells. Previous research has shown that iPS cells retain some memory of their tissue of origin, which may have important implications for their use in therapeutics. To explore these important potential differences, iPS research must continue to be conducted side by side with human embryonic cell research."
In 2006, researchers discovered that they could coax adult cells into a state that appeared identical to embryonic stem cells and then, just like embryonic stem cells, morph these iPS cells into various tissue. But the process involved inserting genes into cells using retroviruses, which raised the risk the cells could cause cancer. Since then, scientists have been trying to develop safer methods. Several approaches using chemicals or other types of viruses have shown promise. But none has eliminated the safety concerns, and most have been slow and balky.
Cell conversion
The new approach involves molecules known as "messenger RNA" (mRNA), which cells use to create proteins they need carry out vital functions. Working in the laboratory, the researchers created mRNA molecules carrying the instructions for the cell's machinery to produce the four key proteins needed to reprogram into iPS cells.
After tinkering with the mRNA molecules to make signals that the cells would not destroy as dangerous invaders, the researchers found that a daily cocktail of their creations was remarkably fast and efficient at reprogramming the cells. The technique converted the cells in about half the time of previous methods--only about 17 days--with surprising economy--up to 100 times more efficient that the standard approach. "We ended up with so many colonies of cells all over the place that we had to stop the experiment," Rossi said.
Moreover, the cells had not experienced any disturbing changes in their DNA caused by previous methods and appeared much more indistinguishable from embryonic stem cells than iPS cells created using other methods. In addition, the researchers went one step further and showed that they could use the strategy to quickly and easily convert the iPS cells they created into a specific cell types - in this case muscle cells.
"If you put all these things together, several of the major hurdles towards clinical translation of iPS cells are addressed by this technology," Rossi said. "That's what we've very excited about." Others agreed. Lanza, for example, called the approach "almost too good to be true," saying it evoked the magical alchemy of "turning lead into gold." "The ability to safely and efficiently generate patient-specific cells has the potential to transform transplantation medicine," Lanza said.
In an e-mail, stem cell pioneer Shinya Yamanaka of Kyoto University in Japan, who helped discover iPS cells, said he planned to immediately try the technique in his lab. "The standard method to generate [iPS cells] for clinical applications has yet to be established," Yamanaka wrote. "I think this method has the potential for it."
Rossi said the approach should also be useful far beyond stem cells by offering a way to treat any genetic condition in which a protein is missing, deficient or defective.
"It has amazing potential in the therapeutic realm," Rossi said.
Wednesday, September 29, 2010
Found: A Planet Like Earth
Time Magazine - September 29, 2010
Michael D. Lemonick
The star known as Gliese 581 is utterly unremarkable in just about every way you can imagine. It's a red dwarf, the most common type of star in the Milky Way, weighing in at about a third the mass of the Sun. At 20 light years or so away, it's relatively nearby, but not close enough to set any records (it's the 117th closest star to Earth, for what that's worth). You can't even see it without a telescope, so while it lies in direction of Libra, it isn't one of the shining dots you'd connect to form the constellation. It's no wonder that the star's name lacks even a whiff of mystery or romance.
But Gliese 581 does have one distinction — and that's enough to make it the focus of intense scientific attention. At last count, astronomers had identified more than 400 planets orbiting stars beyond the Sun, and Gliese 581 was host to no fewer than four of them — the most populous solar system we know of, aside than our own. That alone would make the star intriguing. But on Wednesday, a team of astronomers announced they'd found two more planets circling the star, bringing the total to six. And one of them, assigned the name Gliese 581g, may be of truly historic significance. (See an illustrated history of Planet Earth.)
For one thing, the planet is only about three or four times as massive as our home world, meaning it probably has a solid surface just like Earth. Much more important, it sits smack in the middle of the so-called habitable zone, orbiting at just the right distance from the star to let water remain liquid rather than freezing solid or boiling away. As far as we know, that's a minimum requirement for the presence of life. For thousands of years, philosophers and scientists have wondered whether other Earths existed out in the cosmos. And since the first, very un-Eearthlike extrasolar planet was discovered in 1995, astronomers have been inching closer to answering that question. Now, they've evidently succeeded (although to be clear, there's no way at this point to determine whether there actually is life on the new planet).
"We're pretty excited about it," admits Steve Vogt, of the University of California, Santa Cruz, a member of the team, in a masterpiece of understatement. "I think this is what everyone's been after for the past 15 years." (See the top 50 space moments since Sputnik.)
Planetary scientist James Kasting, of Penn State University, who wasn't involved with the discovery, agrees. "I think they've scooped the Kepler people," he says. Kasting refers to the Kepler space telescope, launched into space early last year on a mission to determine how common Earthlike planets might be. The "Kepler people" have a number of candidate Earths in the can, but are still working to confirm them. (See pictures of Earth from space.)
Being first isn't the main reason Vogt is excited, however. "Someone had to be first," he says. "But this is right next door to us. That's the big result." What's particularly big about it is a matter of simple arithmetic. With only 116 stars closer to Earth than this one, it was hardly a sure thing that so small a sample group would produce two habitable planets, including Earth. And two such planets may be an undercount, Vogt says, since just nine out of those 100-plus stars have been studied in any detail. Indeed, one of Gliese 581g's sister planets, known as Gliese 581d (OK, they truly don't put a lot of creative energy into naming these things) could conceivably be a habitable world itself.
One of the four planets known to orbit Gliese 581 before the latest discovery, 581d was found by a team of Swiss astronomers in 2007 and was thought to be outside the habitable zone, and thus too cold for liquid water. But a reanalysis last year brought it into the zone, albeit just barely. The problem is, Gliese 581d is also too big to be Earthlike; it's probably made mostly of nonwater ice, like Neptune and Uranus, which makes a poorer candidate for life than 581g.
Lost in the excitement over possible life on the new world is what a remarkable achievement its mere discovery was. Detecting a planet this small is monstrously hard—and would have been impossible when Vogt and co-discoverer Paul Butler, of the Carnegie Institution of Washington first got into the planet-hunting game in the early 1990s. The instruments you use to detect tiny back-and-forth motions in the star — motions caused by the orbiting planet's gravitational tugs, which are often the only way to infer that the worlds exist at all—simply weren't sensitive enough. Since then, though, says Vogt, "I've been busting my gut to improve the instruments, and Paul has been busting his got to do the observations." In all, those observations span more than 200 nights on the giant Keck I telescope in Hawaii over 11 years, supplemented by observations from the Geneva group — and that painstaking work finally confirmed 581g's existence.
None of this proves that there actually is water on Gliese 581g. "Those are things we just have to speculate about," says Vogt. But he goes on to point out that there's water pretty much everywhere else you look. "There's water on Earth," he says, "and on the Moon, and Mars, and on Jupiter's moon Europa and Saturn's moon Enceladus, and in interstellar space. There's enough water produced in the Orion Nebula every 24 seconds to fill the Earth's oceans."
It's not hard to imagine, in other words, that Gliese 581g might have plenty of water as well. "It could have quite a good ocean," Vogt says. Certainly, it could still be a sterile, non-biological ocean. But unlike any planet found until now, there's nothing to rule out the idea that could also be teeming with life.
Read more: http://www.time.com/time/health/article/0,8599,2022489,00.html?hpt=T2#ixzz10y6BNV3G
Michael D. Lemonick
The star known as Gliese 581 is utterly unremarkable in just about every way you can imagine. It's a red dwarf, the most common type of star in the Milky Way, weighing in at about a third the mass of the Sun. At 20 light years or so away, it's relatively nearby, but not close enough to set any records (it's the 117th closest star to Earth, for what that's worth). You can't even see it without a telescope, so while it lies in direction of Libra, it isn't one of the shining dots you'd connect to form the constellation. It's no wonder that the star's name lacks even a whiff of mystery or romance.
But Gliese 581 does have one distinction — and that's enough to make it the focus of intense scientific attention. At last count, astronomers had identified more than 400 planets orbiting stars beyond the Sun, and Gliese 581 was host to no fewer than four of them — the most populous solar system we know of, aside than our own. That alone would make the star intriguing. But on Wednesday, a team of astronomers announced they'd found two more planets circling the star, bringing the total to six. And one of them, assigned the name Gliese 581g, may be of truly historic significance. (See an illustrated history of Planet Earth.)
For one thing, the planet is only about three or four times as massive as our home world, meaning it probably has a solid surface just like Earth. Much more important, it sits smack in the middle of the so-called habitable zone, orbiting at just the right distance from the star to let water remain liquid rather than freezing solid or boiling away. As far as we know, that's a minimum requirement for the presence of life. For thousands of years, philosophers and scientists have wondered whether other Earths existed out in the cosmos. And since the first, very un-Eearthlike extrasolar planet was discovered in 1995, astronomers have been inching closer to answering that question. Now, they've evidently succeeded (although to be clear, there's no way at this point to determine whether there actually is life on the new planet).
"We're pretty excited about it," admits Steve Vogt, of the University of California, Santa Cruz, a member of the team, in a masterpiece of understatement. "I think this is what everyone's been after for the past 15 years." (See the top 50 space moments since Sputnik.)
Planetary scientist James Kasting, of Penn State University, who wasn't involved with the discovery, agrees. "I think they've scooped the Kepler people," he says. Kasting refers to the Kepler space telescope, launched into space early last year on a mission to determine how common Earthlike planets might be. The "Kepler people" have a number of candidate Earths in the can, but are still working to confirm them. (See pictures of Earth from space.)
Being first isn't the main reason Vogt is excited, however. "Someone had to be first," he says. "But this is right next door to us. That's the big result." What's particularly big about it is a matter of simple arithmetic. With only 116 stars closer to Earth than this one, it was hardly a sure thing that so small a sample group would produce two habitable planets, including Earth. And two such planets may be an undercount, Vogt says, since just nine out of those 100-plus stars have been studied in any detail. Indeed, one of Gliese 581g's sister planets, known as Gliese 581d (OK, they truly don't put a lot of creative energy into naming these things) could conceivably be a habitable world itself.
One of the four planets known to orbit Gliese 581 before the latest discovery, 581d was found by a team of Swiss astronomers in 2007 and was thought to be outside the habitable zone, and thus too cold for liquid water. But a reanalysis last year brought it into the zone, albeit just barely. The problem is, Gliese 581d is also too big to be Earthlike; it's probably made mostly of nonwater ice, like Neptune and Uranus, which makes a poorer candidate for life than 581g.
Lost in the excitement over possible life on the new world is what a remarkable achievement its mere discovery was. Detecting a planet this small is monstrously hard—and would have been impossible when Vogt and co-discoverer Paul Butler, of the Carnegie Institution of Washington first got into the planet-hunting game in the early 1990s. The instruments you use to detect tiny back-and-forth motions in the star — motions caused by the orbiting planet's gravitational tugs, which are often the only way to infer that the worlds exist at all—simply weren't sensitive enough. Since then, though, says Vogt, "I've been busting my gut to improve the instruments, and Paul has been busting his got to do the observations." In all, those observations span more than 200 nights on the giant Keck I telescope in Hawaii over 11 years, supplemented by observations from the Geneva group — and that painstaking work finally confirmed 581g's existence.
None of this proves that there actually is water on Gliese 581g. "Those are things we just have to speculate about," says Vogt. But he goes on to point out that there's water pretty much everywhere else you look. "There's water on Earth," he says, "and on the Moon, and Mars, and on Jupiter's moon Europa and Saturn's moon Enceladus, and in interstellar space. There's enough water produced in the Orion Nebula every 24 seconds to fill the Earth's oceans."
It's not hard to imagine, in other words, that Gliese 581g might have plenty of water as well. "It could have quite a good ocean," Vogt says. Certainly, it could still be a sterile, non-biological ocean. But unlike any planet found until now, there's nothing to rule out the idea that could also be teeming with life.
Read more: http://www.time.com/time/health/article/0,8599,2022489,00.html?hpt=T2#ixzz10y6BNV3G
Saturday, September 25, 2010
UFO Malmstrom AFB Montana 1967
Former Air Force Officers: UFOs Tampered With Nuclear Missiles
Lee Speigel Contributor
AOL News
(Sept. 25, 2010) -- Former U.S. Air Force officers and a former enlisted man are about to break many years of silence about an alarming series of UFO encounters at nuclear weapons sites -- incidents officially kept secret for decades.
When the group appears at a press conference at the National Press Club in Washington, D.C., on Monday, it will offer testimony about events so chilling, it will seem like a day at a science fiction movie festival.
To put you in the mood for the stories that will soon unfold, we're presenting one here, involving former Air Force Capt. Robert Salas, one of the hosts of the Washington event.
Former Air Force Capt. Robert Salas says he was involved in a 1967 incident at Malmstrom Air Force Base in Montana in which a UFO reportedly tampered with nuclear missiles.
Salas, co-author of "Faded Giant" (BookSurge Publishing), was a first lieutenant in 1967, serving as a missile-launch officer while stationed at Malmstrom Air Force Base in Montana. On March 16, 1967, Salas was 60 feet below ground working a 24-hour shift monitoring a launch-control center outfitted with 10 nuclear Minuteman missiles. "I got a call from the topside guard, telling me they were watching some strange lights flying around in the sky, making odd maneuvers. They didn't think they were airplanes because they were going very fast, turning on a dime and not making a bit of noise," Salas told AOL News.
"A few minutes later, he called back, this time screaming into the phone, scared to death, and he said, 'Sir, I'm looking out my front window and there is a glowing red oval-shaped object hovering right above the front gate, and I've got all the guards out here with their weapons drawn.' "
The guard told Salas the UFO was approximately 30 to 40 feet in diameter with a very bright, pulsating light. When the guard asked what they should do next, Salas' immediate response was that they had to do whatever was necessary to protect the nuclear missile area, "so basically, I was giving them permission to use whatever force they needed to use to keep anything out."
As Salas started to inform his duty partner and commander about what was going on 60 feet above them, something chilling happened. "All of a sudden, we started getting bells and whistles going off. As we looked at the display board in front of us, sure enough, the missiles began going into an unlaunchable, or no-go, mode. They couldn't be launched -- it went from green to red.
"We also had a couple of security violations, meaning there were lights indicating some kind of intrusion at the missile sites, where the missiles were actually located, about a mile or two away from the launch control facility." Salas said they immediately performed a system checklist to see what was wrong and to determine how it was possible that 10 nuclear missiles could suddenly be deactivated.
"We were getting mostly guidance and control systems failure, and when I called the guard again, he told me the UFO just left and took off at high speed. So I ordered the guards to go out to the missile sites, and while they were out there, they saw the object again at one of the launch facilities.
"It scared them to death again, and they actually lost radio contact while they were near the object and then they returned to the base. I later learned they never returned to security guard duty."
Salas said it was extraordinary that they lost so many missiles at the same time. Isolated mishaps had made a single missile go "unlaunchable," but never 10 at once. And never 10 at once during a UFO sighting. As a result of the incident, the missiles had to be fixed to get them all back into launch mode.
Interesting aftermath to the story: Salas returned to the base and was ordered to report to his squadron commander where he also met with a member of the Air Force Office of Special Investigations, or AFOSI. Salas first asked if what they had just been through was some sort of Air Force exercise, and says he was told "absolutely not."
"After we told them our recollection of the incident, the AFOSI captain wanted us to sign papers, saying we'd never talk about this and swear we wouldn't even talk to our wives or any of the other airmen on the base -- nobody.
"I felt a little weird about this because all of us who were launch officers had above top-secret clearance, and I asked, 'If this is classified, what's it classified as?' And he said, 'Secret,' and I said, 'Well, we've got above top secret -- why do we have to sign anymore papers?' "
But further information was denied Salas and his men. And what does he think would've happened to him had he gone to the press with the story? "If I went public with this while still in the service, I would've been in Leavenworth [maximum security federal prison], breaking stones into little pebbles."
In 1969, the Air Force ended Project Blue Book, its official program that investigated UFOs. And in 1985, the following information was included in a fact sheet distributed by Wright-Patterson Air Force Base, and this remains the official attitude about UFOs:
(1) No UFO reported, investigated and evaluated by the Air Force has ever given any indication of threat to our national security; (2) There has been no evidence submitted to or discovered by the Air Force that sightings categorized as "unidentified" represent technological developments or principles beyond the range of present-day scientific knowledge; and (3) There has been no evidence indicating that sightings categorized as "unidentified" are extraterrestrial vehicles.
That being said, Salas and his colleagues maintain that if enough military eyewitnesses come forward, it can be proved that there's more to UFOs than officials have led the public to believe.
After the extraordinary events at Malmstrom Air Force base where it appears a UFO may have been responsible for shutting down 10 nuclear missiles, Salas wonders if the military has any legal authority to command its subordinates not to talk about something this significant -- something that he maintains represents a technology not known today.
The UFO "had to somehow send a signal to penetrate 60 feet of earth and concrete and also to penetrate the cable system, which is triply shielded cables, and inject some kind of a signal into the system. That's fantastic."
So, why, after so many years of keeping quiet, are former military personnel coming forward to talk about their experiences, as Salas and his Air Force colleagues are doing on Monday? He says the people who will talk in Washington are "just the tip of the iceberg."
"I believe in the extraterrestrial hypothesis, and I think, in this instance, these objects were not constructed on planet Earth."
Lee Speigel Contributor
AOL News
(Sept. 25, 2010) -- Former U.S. Air Force officers and a former enlisted man are about to break many years of silence about an alarming series of UFO encounters at nuclear weapons sites -- incidents officially kept secret for decades.
When the group appears at a press conference at the National Press Club in Washington, D.C., on Monday, it will offer testimony about events so chilling, it will seem like a day at a science fiction movie festival.
To put you in the mood for the stories that will soon unfold, we're presenting one here, involving former Air Force Capt. Robert Salas, one of the hosts of the Washington event.
Former Air Force Capt. Robert Salas says he was involved in a 1967 incident at Malmstrom Air Force Base in Montana in which a UFO reportedly tampered with nuclear missiles.
Salas, co-author of "Faded Giant" (BookSurge Publishing), was a first lieutenant in 1967, serving as a missile-launch officer while stationed at Malmstrom Air Force Base in Montana. On March 16, 1967, Salas was 60 feet below ground working a 24-hour shift monitoring a launch-control center outfitted with 10 nuclear Minuteman missiles. "I got a call from the topside guard, telling me they were watching some strange lights flying around in the sky, making odd maneuvers. They didn't think they were airplanes because they were going very fast, turning on a dime and not making a bit of noise," Salas told AOL News.
"A few minutes later, he called back, this time screaming into the phone, scared to death, and he said, 'Sir, I'm looking out my front window and there is a glowing red oval-shaped object hovering right above the front gate, and I've got all the guards out here with their weapons drawn.' "
The guard told Salas the UFO was approximately 30 to 40 feet in diameter with a very bright, pulsating light. When the guard asked what they should do next, Salas' immediate response was that they had to do whatever was necessary to protect the nuclear missile area, "so basically, I was giving them permission to use whatever force they needed to use to keep anything out."
As Salas started to inform his duty partner and commander about what was going on 60 feet above them, something chilling happened. "All of a sudden, we started getting bells and whistles going off. As we looked at the display board in front of us, sure enough, the missiles began going into an unlaunchable, or no-go, mode. They couldn't be launched -- it went from green to red.
"We also had a couple of security violations, meaning there were lights indicating some kind of intrusion at the missile sites, where the missiles were actually located, about a mile or two away from the launch control facility." Salas said they immediately performed a system checklist to see what was wrong and to determine how it was possible that 10 nuclear missiles could suddenly be deactivated.
"We were getting mostly guidance and control systems failure, and when I called the guard again, he told me the UFO just left and took off at high speed. So I ordered the guards to go out to the missile sites, and while they were out there, they saw the object again at one of the launch facilities.
"It scared them to death again, and they actually lost radio contact while they were near the object and then they returned to the base. I later learned they never returned to security guard duty."
Salas said it was extraordinary that they lost so many missiles at the same time. Isolated mishaps had made a single missile go "unlaunchable," but never 10 at once. And never 10 at once during a UFO sighting. As a result of the incident, the missiles had to be fixed to get them all back into launch mode.
Interesting aftermath to the story: Salas returned to the base and was ordered to report to his squadron commander where he also met with a member of the Air Force Office of Special Investigations, or AFOSI. Salas first asked if what they had just been through was some sort of Air Force exercise, and says he was told "absolutely not."
"After we told them our recollection of the incident, the AFOSI captain wanted us to sign papers, saying we'd never talk about this and swear we wouldn't even talk to our wives or any of the other airmen on the base -- nobody.
"I felt a little weird about this because all of us who were launch officers had above top-secret clearance, and I asked, 'If this is classified, what's it classified as?' And he said, 'Secret,' and I said, 'Well, we've got above top secret -- why do we have to sign anymore papers?' "
But further information was denied Salas and his men. And what does he think would've happened to him had he gone to the press with the story? "If I went public with this while still in the service, I would've been in Leavenworth [maximum security federal prison], breaking stones into little pebbles."
In 1969, the Air Force ended Project Blue Book, its official program that investigated UFOs. And in 1985, the following information was included in a fact sheet distributed by Wright-Patterson Air Force Base, and this remains the official attitude about UFOs:
(1) No UFO reported, investigated and evaluated by the Air Force has ever given any indication of threat to our national security; (2) There has been no evidence submitted to or discovered by the Air Force that sightings categorized as "unidentified" represent technological developments or principles beyond the range of present-day scientific knowledge; and (3) There has been no evidence indicating that sightings categorized as "unidentified" are extraterrestrial vehicles.
That being said, Salas and his colleagues maintain that if enough military eyewitnesses come forward, it can be proved that there's more to UFOs than officials have led the public to believe.
After the extraordinary events at Malmstrom Air Force base where it appears a UFO may have been responsible for shutting down 10 nuclear missiles, Salas wonders if the military has any legal authority to command its subordinates not to talk about something this significant -- something that he maintains represents a technology not known today.
The UFO "had to somehow send a signal to penetrate 60 feet of earth and concrete and also to penetrate the cable system, which is triply shielded cables, and inject some kind of a signal into the system. That's fantastic."
So, why, after so many years of keeping quiet, are former military personnel coming forward to talk about their experiences, as Salas and his Air Force colleagues are doing on Monday? He says the people who will talk in Washington are "just the tip of the iceberg."
"I believe in the extraterrestrial hypothesis, and I think, in this instance, these objects were not constructed on planet Earth."
Saturday, July 31, 2010
Milky Way is Rich in Planets Like Earth
Our galaxy is rich in Earth-sized planets
July 27, 2010 8:24 a.m. EDT
Planets may answer age-old questions
* Dimitar Sasselov: Earth-sized planets are plentiful in the galaxy
* He says planets of such size are suited for the chemical processes that can produce life
* Sasselov says biologists are finding clues to origin of life in laboratories
* He says Earth life is notably old, representing nearly a third of age of universe
Editor's note: TED, a nonprofit organization devoted to "Ideas Worth Spreading," hosts talks on many subjects and makes them available through its website.
(CNN) -- Since the time of Nicolaus Copernicus five centuries ago, people have wondered whether there are other planets like Earth in the universe. Today scientists are closer than ever to an answer -- and it appears to be that the Milky Way galaxy is rich in Earth-sized planets, according to astronomer Dimitar Sasselov.
Drawing on new findings from a NASA telescope, he told the TED Global conference in Oxford, England earlier this month that nearly 150 Earth-sized planets have been detected so far. He estimated that the overall number of planets in the galaxy with "similar conditions to the conditions that we experience here on Earth is pretty staggering. It's about 100 million such planets."
A Bulgarian-born scientist with Ph.D.s in astronomy and physics, Sasselov is a professor of astronomy and director of the Harvard Origins of Life Initiative, which brings together scientists from many disciplines to explore how life began. He titled his talk at the Oxford conference: "On Completing the Copernican Revolution."
Until technology was developed to detect planets outside the solar system 15 years ago, scientists were only able to speculate about the existence of Earth-like planets. The new technology paid off in the discovery of some 500 planets.
The disappointing fact though was that very few of the newly identified planets were the size of Earth. "There was of course an explanation for it. We only see the big planets. So that's why most of those planets are really in the category of 'like Jupiter,' " he said.
There was no indication that these large planets were suitable for life to begin.
"We were still back where Copernicus was. We didn't have any evidence whether planets like the Earth are out there," Sasselov said. "And we do care about planets like the Earth because by now we understood that life as a chemical system really needs a smaller planet with water and with rocks and with a lot of complex chemistry to originate, to emerge, to survive. And we didn't have the evidence for that."
In March 2009, NASA launched Kepler, a telescope-carrying satellite that can detect the dimming of light caused by a planet orbiting around a star.
"All the stars for Kepler are just points of light," Sasselov said. "But we learn a lot from that, not only that there is a planet there, but we also learn its size. How much of the light is being dimmed depends on how big the planet is. We learn about its orbit, the period of its orbit and so on."
The discovery of many potential planets means "we can go and study them -- remotely, of course -- with all the techniques that we already have tested in the past five years. We can find what they're made of, would their atmospheres have water, carbon dioxide, methane." At the same time, Sasselov believes, scientists can make progress in the laboratory on better understanding how chemicals can produce life.
"And in one of our labs, Jack Szostak's labs, it was a series of experiments in the last four years that showed that the environments -- which are very common on planets, on certain types of planets like the Earth -- where you have some liquid water and some clays, you actually end up with naturally available molecules which spontaneously form bubbles. But those bubbles have membranes very similar to the membrane of every cell of every living thing on Earth. .... And they really help molecules, like nucleic acids, like RNA and DNA, stay inside, develop, change, divide and do some of the processes that we call life."
Copernicus is famous for the then-revolutionary idea that the Earth orbits the sun rather than that the universe is centered around Earth. But Sasselov pointed out that with the Copernican revolution came a humbling sense of mankind's insignificance in the universe.
"You've all learned that in school -- how small the Earth is compared to the immense universe. And the bigger the telescope, the bigger that universe becomes. ... So in space, the Earth is very small. To demonstrate the minuteness of life on Earth, Sasselov took off his tie.
"Can you imagine how small it is? Let me try it. OK, let's say this is the size of the observable universe, with all the galaxies, with all the stars. Do you know what the size of life in this necktie will be?
"It will be the size of a single, small atom. It is unimaginably small. ... But that's not the whole story, you see."
The other dimension of life on Earth is time -- and life has existed for a good portion, nearly a third, of the time the universe is believed to have existed, Sasselov said.
"This is not insignificant. This is very significant. So life might be insignificant in size, but it is not insignificant in time. Life and the universe compare to each other like a child and a parent, parent and offspring.
"So what does this tell us? This tells us that that insignificance paradigm that we somehow got to learn from the Copernican principle, it's all wrong. There is immense, powerful, potential in life in this universe -- especially now that we know that places like the Earth are common. And that potential, that powerful potential, is also our potential, of you and me.
"And if we are to be stewards of our planet Earth and its biosphere, we better understand the cosmic significance and do something about it. And the good news is we can actually indeed do it. "
July 27, 2010 8:24 a.m. EDT
Planets may answer age-old questions
* Dimitar Sasselov: Earth-sized planets are plentiful in the galaxy
* He says planets of such size are suited for the chemical processes that can produce life
* Sasselov says biologists are finding clues to origin of life in laboratories
* He says Earth life is notably old, representing nearly a third of age of universe
Editor's note: TED, a nonprofit organization devoted to "Ideas Worth Spreading," hosts talks on many subjects and makes them available through its website.
(CNN) -- Since the time of Nicolaus Copernicus five centuries ago, people have wondered whether there are other planets like Earth in the universe. Today scientists are closer than ever to an answer -- and it appears to be that the Milky Way galaxy is rich in Earth-sized planets, according to astronomer Dimitar Sasselov.
Drawing on new findings from a NASA telescope, he told the TED Global conference in Oxford, England earlier this month that nearly 150 Earth-sized planets have been detected so far. He estimated that the overall number of planets in the galaxy with "similar conditions to the conditions that we experience here on Earth is pretty staggering. It's about 100 million such planets."
A Bulgarian-born scientist with Ph.D.s in astronomy and physics, Sasselov is a professor of astronomy and director of the Harvard Origins of Life Initiative, which brings together scientists from many disciplines to explore how life began. He titled his talk at the Oxford conference: "On Completing the Copernican Revolution."
Until technology was developed to detect planets outside the solar system 15 years ago, scientists were only able to speculate about the existence of Earth-like planets. The new technology paid off in the discovery of some 500 planets.
The disappointing fact though was that very few of the newly identified planets were the size of Earth. "There was of course an explanation for it. We only see the big planets. So that's why most of those planets are really in the category of 'like Jupiter,' " he said.
There was no indication that these large planets were suitable for life to begin.
"We were still back where Copernicus was. We didn't have any evidence whether planets like the Earth are out there," Sasselov said. "And we do care about planets like the Earth because by now we understood that life as a chemical system really needs a smaller planet with water and with rocks and with a lot of complex chemistry to originate, to emerge, to survive. And we didn't have the evidence for that."
In March 2009, NASA launched Kepler, a telescope-carrying satellite that can detect the dimming of light caused by a planet orbiting around a star.
"All the stars for Kepler are just points of light," Sasselov said. "But we learn a lot from that, not only that there is a planet there, but we also learn its size. How much of the light is being dimmed depends on how big the planet is. We learn about its orbit, the period of its orbit and so on."
The discovery of many potential planets means "we can go and study them -- remotely, of course -- with all the techniques that we already have tested in the past five years. We can find what they're made of, would their atmospheres have water, carbon dioxide, methane." At the same time, Sasselov believes, scientists can make progress in the laboratory on better understanding how chemicals can produce life.
"And in one of our labs, Jack Szostak's labs, it was a series of experiments in the last four years that showed that the environments -- which are very common on planets, on certain types of planets like the Earth -- where you have some liquid water and some clays, you actually end up with naturally available molecules which spontaneously form bubbles. But those bubbles have membranes very similar to the membrane of every cell of every living thing on Earth. .... And they really help molecules, like nucleic acids, like RNA and DNA, stay inside, develop, change, divide and do some of the processes that we call life."
Copernicus is famous for the then-revolutionary idea that the Earth orbits the sun rather than that the universe is centered around Earth. But Sasselov pointed out that with the Copernican revolution came a humbling sense of mankind's insignificance in the universe.
"You've all learned that in school -- how small the Earth is compared to the immense universe. And the bigger the telescope, the bigger that universe becomes. ... So in space, the Earth is very small. To demonstrate the minuteness of life on Earth, Sasselov took off his tie.
"Can you imagine how small it is? Let me try it. OK, let's say this is the size of the observable universe, with all the galaxies, with all the stars. Do you know what the size of life in this necktie will be?
"It will be the size of a single, small atom. It is unimaginably small. ... But that's not the whole story, you see."
The other dimension of life on Earth is time -- and life has existed for a good portion, nearly a third, of the time the universe is believed to have existed, Sasselov said.
"This is not insignificant. This is very significant. So life might be insignificant in size, but it is not insignificant in time. Life and the universe compare to each other like a child and a parent, parent and offspring.
"So what does this tell us? This tells us that that insignificance paradigm that we somehow got to learn from the Copernican principle, it's all wrong. There is immense, powerful, potential in life in this universe -- especially now that we know that places like the Earth are common. And that potential, that powerful potential, is also our potential, of you and me.
"And if we are to be stewards of our planet Earth and its biosphere, we better understand the cosmic significance and do something about it. And the good news is we can actually indeed do it. "
Thursday, July 22, 2010
Monster Star Discovered
Scientists discover monster star
By Moni Basu, CNN
July 21, 2010 5:54 p.m. EDT
The massive star is in the Tarantula Nebula, 165,000 light years from our galaxy.
(CNN) -- Imagine a star so luminous that it would burn the Earth up if it were anywhere near, a star that outshines the sun as much as the sun outshines the moon. A monster even in the abyss of space.
The star is not some scientist's celestial dream. Astronomers used a Very Large Telescope -- the instrument's official name -- to detect the most massive star discovered to date. In scientific lingo, it's a "hypergiant."
Led by Paul Crowther, professor of astrophysics at England's University of Sheffield, the team of astronomers studied two young clusters of stars, NGC 3603 and RMC 136a.
R136a1, found in the RMC 136a cluster, is 10 million times brighter than the sun and is the heaviest star ever found, Crowther said Wednesday, with a mass that is roughly 265 times more than the sun. It was born even heavier, with a solar mass of 320. Astronomers previously thought 150 to be the upper limit.
Several of the stars studied had surface temperatures of 40,000 degrees, more than seven times hotter than the sun.
R136a1 is rare and resides in another galaxy called the Large Magellanic Cloud. Its home is more than 165,000 light years away from Earth's Milky Way galaxy. As such, said Crowther, it is not visible to the naked eye, nor with a rooftop telescope.
"Owing to the rarity of these monsters, I think it is unlikely that this new record will be broken any time soon," Crowther said.
Crowther's team used the sophisticated infrared equipment on the Very Large Telescope in a European Southern Observatory facility in Chile as well as data collected from the Hubble Space Telescope to detect the colossal star. The telescope is considered the world's "biggest eye on the sky" and is 8 meters (26 feet) in diameter.
The research was published in the current issue of the British scientific journal The Monthly Notices of the Royal Astronomical Society.
"Unlike people, these kind of stars are massive when they are babies," Crowther told CNN. "They lose weight as they get older."
At over a million years old, the star is already middle-aged, Crowther said, and could easily be a poster child for WeightWatchers, having shed a fifth of its initial mass over time because of powerful winds.
In another million years -- a brief life span compared to the sun's 5 billion years of existence -- the giant star will probably explode as a supernova. It won't be noticeable on Earth because it's so far away.
Crowther, excited about the new find, had to find simple terminology to describe it to his 6-year-old son Billy. Billy, in turn, wanted dad to name the monster star after him.
That might have sounded a whole lot better than R136a1, but nonetheless, a star is born.
By Moni Basu, CNN
July 21, 2010 5:54 p.m. EDT
The massive star is in the Tarantula Nebula, 165,000 light years from our galaxy.
(CNN) -- Imagine a star so luminous that it would burn the Earth up if it were anywhere near, a star that outshines the sun as much as the sun outshines the moon. A monster even in the abyss of space.
The star is not some scientist's celestial dream. Astronomers used a Very Large Telescope -- the instrument's official name -- to detect the most massive star discovered to date. In scientific lingo, it's a "hypergiant."
Led by Paul Crowther, professor of astrophysics at England's University of Sheffield, the team of astronomers studied two young clusters of stars, NGC 3603 and RMC 136a.
R136a1, found in the RMC 136a cluster, is 10 million times brighter than the sun and is the heaviest star ever found, Crowther said Wednesday, with a mass that is roughly 265 times more than the sun. It was born even heavier, with a solar mass of 320. Astronomers previously thought 150 to be the upper limit.
Several of the stars studied had surface temperatures of 40,000 degrees, more than seven times hotter than the sun.
R136a1 is rare and resides in another galaxy called the Large Magellanic Cloud. Its home is more than 165,000 light years away from Earth's Milky Way galaxy. As such, said Crowther, it is not visible to the naked eye, nor with a rooftop telescope.
"Owing to the rarity of these monsters, I think it is unlikely that this new record will be broken any time soon," Crowther said.
Crowther's team used the sophisticated infrared equipment on the Very Large Telescope in a European Southern Observatory facility in Chile as well as data collected from the Hubble Space Telescope to detect the colossal star. The telescope is considered the world's "biggest eye on the sky" and is 8 meters (26 feet) in diameter.
The research was published in the current issue of the British scientific journal The Monthly Notices of the Royal Astronomical Society.
"Unlike people, these kind of stars are massive when they are babies," Crowther told CNN. "They lose weight as they get older."
At over a million years old, the star is already middle-aged, Crowther said, and could easily be a poster child for WeightWatchers, having shed a fifth of its initial mass over time because of powerful winds.
In another million years -- a brief life span compared to the sun's 5 billion years of existence -- the giant star will probably explode as a supernova. It won't be noticeable on Earth because it's so far away.
Crowther, excited about the new find, had to find simple terminology to describe it to his 6-year-old son Billy. Billy, in turn, wanted dad to name the monster star after him.
That might have sounded a whole lot better than R136a1, but nonetheless, a star is born.
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