WASHINGTON – Earth seems to have its first fuzzy photos of alien planets outside our solar system, images captured by two teams of astronomers. The pictures show four likely planets that appear as specks of white, nearly indecipherable except to the most eagle-eyed experts. All are trillions of miles away — three of them orbiting the same star, and the fourth circling a different star.
None of the four giant gaseous planets are remotely habitable or remotely like Earth. But they raise the possibility of others more hospitable.
It's only a matter of time before "we get a dot that's blue and Earthlike," said astronomer Bruce Macintosh of the Lawrence Livermore National Lab. He led one of the two teams of photographers.
"It is a step on that road to understand if there are other planets like Earth and potentially life out there," he said.
Macintosh's team used two ground-based telescopes, while the second team relied on photos from the 18-year-old Hubble Space Telescope to gather images of the exoplanets — planets that don't circle our sun. The research from both teams was published in Thursday's online edition of the journal Science.
In the past 13 years, scientists have discovered more than 300 planets outside our solar system, but they have done so indirectly, by measuring changes in gravity, speed or light around stars.
NASA's space sciences chief Ed Weiler said the actual photos are important. He compared it to a hunt for elusive elephants: "For years we've been hearing the elephants, finding the tracks, seeing the trees knocked down by them, but we've never been able to snap a picture. Now we have a picture."
In a news conference Thursday, Weiler said this fulfills the last of the major goals that NASA had for the Hubble telescope before it launched in 1990: "This is an 18 1/2-year dream come true."
There are disputes about whether these are the first exoplanet photos. Others have made earlier claims, but those pictures haven't been confirmed as planets or universally accepted yet. The photos released Thursday are being published in a scientifically prominent journal, but that still hasn't convinced all the experts. Alan Boss, an exoplanet expert at the Carnegie Institution of Washington, and Harvard exoplanet hunter Lisa Kaltenegger both said more study is needed to confirm these photos are proven planets and not just brown dwarf stars.
(taken from Yahoo News, 14th November 2008)
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