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."
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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, October 28, 2010
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.
Thursday, May 20, 2010
Cell Based on Man-Made Genetic Instructions
Scientists create cell based on man-made genetic instructions
Washington Post
By David Brown
Friday, May 21, 2010
Scientists reported Thursday that they have created a cell controlled entirely by man-made genetic instructions -- the latest step toward creating life from scratch. The achievement is a landmark in the emerging field of "synthetic biology," which aims to control the behavior of organisms by manipulating their genes.
Although the ultimate goal of creating artificial organisms is still far off, the experiment points to a future in which microbes could be manufactured with novel functions, such as the ability to digest pollutants or produce fuels. Some ethicists fear that the strategy could also be used to produce biological weapons and other dangerous life forms.
In a paper published online by the journal Science, researchers from the J. Craig Venter Institute described using off-the-shelf chemicals and the DNA sequence of Mycoplasma mycoides's genes to make an artificial copy of the bacterium's genome. The scientists then transplanted that genome into the cell of a different (but closely related) microbe.
The donor genome reprogrammed the recipient cell, which went on to replicate and divide. The result was new colonies of Mycoplasma mycoides.
"We think these are the first synthetic cells that are self-replicating and whose genetic heritage started in the computer. That changes conceptually how I think about life," said J. Craig Venter, 63, who gained fame a decade ago as the co-sequencer of the human genome. His institute has laboratories and offices in Rockville and San Diego.
Other scientists characterize the experiment in less revolutionary terms. They say that only the genome was synthetic; the recipient cell was equipped by nature and billions of years of evolution to make sense of the genes it received and turn them on. Still, they praised Venter's 24-member team for showing that such a transplant was feasible.
"From a technical standpoint, this is clearly a very important advance," said Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health. "It is a milestone in synthetic biology," said Gregory Stephanopoulos, a professor of chemical and engineering and biotechnology at MIT. "Over the long term, it will have an impact, although over the short term, not so much."
The Venter team stopped short of creating new cells with new functions. Instead, it manufactured a Mycoplasma mycoides genome that was virtually identical to the natural one and used it to make cells that were also nearly indistinguishable from the natural cells.
In that sense, the experiment's success is more symbolic than practical. It is unlikely to have any immediate effect on the biotech world, which for more than two decades has used various methods of recombinant DNA technology to manipulate to manufacture drugs, produce pest-resistant crops and enhance the nutritional value of food.
The development nonetheless engaged the attention of President Obama, who on Thursday asked the Presidential Commission for the Study of Bioethical Issues to "undertake, as its first order of business, a study of the implications of this scientific milestone, as well as other advances that may lie ahead in this field of research."
The early consensus is that Venter's achievement poses no hazards beyond those that exist with current modes of moving or tweaking genes.
It does not represent an additional threat for biological weapons," said Paul S. Keim, a molecular biologist at Northern Arizona University who chairs the National Science Advisory Board for Biosecurity, a 17-member committee of academic scientists and federal officials that advises the government on "dual use" technologies that can be employed for both good and harmful purposes. Keim said that Venter has been transparent about the direction of his research and had provided the board with a copy of the new paper before it was published.
Under current methods of gene manipulation, scientists harvest a gene from one cell through a process called "cloning" and put it into a transfer vehicle. That vehicle (often a subcellular structure called a plasmid) is then inserted into a different cell, which activates the gene, leading to the production of a scientifically or commercially useful protein.
Venter's project was more ambitious. The scientists knew the order of the 1,089,202 DNA letters ("nucleotides") of Mycoplasma mycoides's genome. They built it in pieces, nucleotide-by-nucleotide. Then they stitched the pieces together.
The result was a man-made copy of the genome that Mycoplasma mycoides produces naturally. However, it was not an exact duplicate. Fourteen of the bacterium's 850 genes were altered or deleted during the experiment -- 12 intentionally, two accidentally. None of those was essential for the bacterium's survival.
Parts of the process remain mysterious even to the scientists. For example, the cells receiving the synthetic genome also contained a natural genome, and the two genomes were sent into different "daughter" cells when the bacterium divided.
"We don't know exactly what happens during the genome transplantation experiment," said Daniel Gibson, 33, a molecular biologist at the Venter Institute who did much of the work. It does not represent an additional threat for biological weapons," said Paul S. Keim, a molecular biologist at Northern Arizona University who chairs the National Science Advisory Board for Biosecurity, a 17-member committee of academic scientists and federal officials that advises the government on "dual use" technologies that can be employed for both good and harmful purposes. Keim said that Venter has been transparent about the direction of his research and had provided the board with a copy of the new paper before it was published.
Under current methods of gene manipulation, scientists harvest a gene from one cell through a process called "cloning" and put it into a transfer vehicle. That vehicle (often a subcellular structure called a plasmid) is then inserted into a different cell, which activates the gene, leading to the production of a scientifically or commercially useful protein.
Venter's project was more ambitious. The scientists knew the order of the 1,089,202 DNA letters ("nucleotides") of Mycoplasma mycoides's genome. They built it in pieces, nucleotide-by-nucleotide. Then they stitched the pieces together.
The result was a man-made copy of the genome that Mycoplasma mycoides produces naturally. However, it was not an exact duplicate. Fourteen of the bacterium's 850 genes were altered or deleted during the experiment -- 12 intentionally, two accidentally. None of those was essential for the bacterium's survival.
Parts of the process remain mysterious even to the scientists. For example, the cells receiving the synthetic genome also contained a natural genome, and the two genomes were sent into different "daughter" cells when the bacterium divided.
"We don't know exactly what happens during the genome transplantation experiment," said Daniel Gibson, 33, a molecular biologist at the Venter Institute who did much of the work.
Washington Post
By David Brown
Friday, May 21, 2010
Scientists reported Thursday that they have created a cell controlled entirely by man-made genetic instructions -- the latest step toward creating life from scratch. The achievement is a landmark in the emerging field of "synthetic biology," which aims to control the behavior of organisms by manipulating their genes.
Although the ultimate goal of creating artificial organisms is still far off, the experiment points to a future in which microbes could be manufactured with novel functions, such as the ability to digest pollutants or produce fuels. Some ethicists fear that the strategy could also be used to produce biological weapons and other dangerous life forms.
In a paper published online by the journal Science, researchers from the J. Craig Venter Institute described using off-the-shelf chemicals and the DNA sequence of Mycoplasma mycoides's genes to make an artificial copy of the bacterium's genome. The scientists then transplanted that genome into the cell of a different (but closely related) microbe.
The donor genome reprogrammed the recipient cell, which went on to replicate and divide. The result was new colonies of Mycoplasma mycoides.
"We think these are the first synthetic cells that are self-replicating and whose genetic heritage started in the computer. That changes conceptually how I think about life," said J. Craig Venter, 63, who gained fame a decade ago as the co-sequencer of the human genome. His institute has laboratories and offices in Rockville and San Diego.
Other scientists characterize the experiment in less revolutionary terms. They say that only the genome was synthetic; the recipient cell was equipped by nature and billions of years of evolution to make sense of the genes it received and turn them on. Still, they praised Venter's 24-member team for showing that such a transplant was feasible.
"From a technical standpoint, this is clearly a very important advance," said Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases at the National Institutes of Health. "It is a milestone in synthetic biology," said Gregory Stephanopoulos, a professor of chemical and engineering and biotechnology at MIT. "Over the long term, it will have an impact, although over the short term, not so much."
The Venter team stopped short of creating new cells with new functions. Instead, it manufactured a Mycoplasma mycoides genome that was virtually identical to the natural one and used it to make cells that were also nearly indistinguishable from the natural cells.
In that sense, the experiment's success is more symbolic than practical. It is unlikely to have any immediate effect on the biotech world, which for more than two decades has used various methods of recombinant DNA technology to manipulate to manufacture drugs, produce pest-resistant crops and enhance the nutritional value of food.
The development nonetheless engaged the attention of President Obama, who on Thursday asked the Presidential Commission for the Study of Bioethical Issues to "undertake, as its first order of business, a study of the implications of this scientific milestone, as well as other advances that may lie ahead in this field of research."
The early consensus is that Venter's achievement poses no hazards beyond those that exist with current modes of moving or tweaking genes.
It does not represent an additional threat for biological weapons," said Paul S. Keim, a molecular biologist at Northern Arizona University who chairs the National Science Advisory Board for Biosecurity, a 17-member committee of academic scientists and federal officials that advises the government on "dual use" technologies that can be employed for both good and harmful purposes. Keim said that Venter has been transparent about the direction of his research and had provided the board with a copy of the new paper before it was published.
Under current methods of gene manipulation, scientists harvest a gene from one cell through a process called "cloning" and put it into a transfer vehicle. That vehicle (often a subcellular structure called a plasmid) is then inserted into a different cell, which activates the gene, leading to the production of a scientifically or commercially useful protein.
Venter's project was more ambitious. The scientists knew the order of the 1,089,202 DNA letters ("nucleotides") of Mycoplasma mycoides's genome. They built it in pieces, nucleotide-by-nucleotide. Then they stitched the pieces together.
The result was a man-made copy of the genome that Mycoplasma mycoides produces naturally. However, it was not an exact duplicate. Fourteen of the bacterium's 850 genes were altered or deleted during the experiment -- 12 intentionally, two accidentally. None of those was essential for the bacterium's survival.
Parts of the process remain mysterious even to the scientists. For example, the cells receiving the synthetic genome also contained a natural genome, and the two genomes were sent into different "daughter" cells when the bacterium divided.
"We don't know exactly what happens during the genome transplantation experiment," said Daniel Gibson, 33, a molecular biologist at the Venter Institute who did much of the work. It does not represent an additional threat for biological weapons," said Paul S. Keim, a molecular biologist at Northern Arizona University who chairs the National Science Advisory Board for Biosecurity, a 17-member committee of academic scientists and federal officials that advises the government on "dual use" technologies that can be employed for both good and harmful purposes. Keim said that Venter has been transparent about the direction of his research and had provided the board with a copy of the new paper before it was published.
Under current methods of gene manipulation, scientists harvest a gene from one cell through a process called "cloning" and put it into a transfer vehicle. That vehicle (often a subcellular structure called a plasmid) is then inserted into a different cell, which activates the gene, leading to the production of a scientifically or commercially useful protein.
Venter's project was more ambitious. The scientists knew the order of the 1,089,202 DNA letters ("nucleotides") of Mycoplasma mycoides's genome. They built it in pieces, nucleotide-by-nucleotide. Then they stitched the pieces together.
The result was a man-made copy of the genome that Mycoplasma mycoides produces naturally. However, it was not an exact duplicate. Fourteen of the bacterium's 850 genes were altered or deleted during the experiment -- 12 intentionally, two accidentally. None of those was essential for the bacterium's survival.
Parts of the process remain mysterious even to the scientists. For example, the cells receiving the synthetic genome also contained a natural genome, and the two genomes were sent into different "daughter" cells when the bacterium divided.
"We don't know exactly what happens during the genome transplantation experiment," said Daniel Gibson, 33, a molecular biologist at the Venter Institute who did much of the work.
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