Earth-Like Planet May Exist
Posted on Sep 13, 2011
European astronomers said Monday that they may have found a celestial body with the right characteristics to host life: a “Goldilocks” planet circling a star at a distance that is not too hot, not too cold, but just right for liquid water to exist.
The planet, which scientists call HD 85512b, is 3.6 times as massive as Earth and is located about 36 light-years away in the constellation Vela. It orbits its star—an orange body about two-thirds as massive as the sun and only one-eighth as luminous—at a quarter the distance Earth circles the sun.
Astronomers could not yet determine details about the composition of the planet nor about its atmosphere, if it has one at all. And they aren’t likely to discover those details anytime soon. The planet is located in a portion of the sky that doesn’t yet have the appropriate telescopes to search for signs of life, and it would take years once they are built (if they are built) to make accurate observations. —BF
The New York Times:
A study led by Dr. Kaltenegger, Dr. Pepe and Dr. Udry concluded that HD 85512b was potentially habitable if it had more than a 50 percent cloud cover.
Dimitar Sasselov of the Center for Astrophysics, who has followed this work but is not part of the team, said that Dr. Kaltenegger and her colleagues made reasonable assumptions. He called the result “very solid” and “a major step in the right direction.”
Others were less impressed by the case for habitability. Sara Seager of the Massachusetts Institute of Technology noted that Dr. Kaltenegger’s model atmospheres were limited to water, carbon dioxide and nitrogen, like the Earth.
“A very terracentric view,” she said in an e-mail.
An illustration of what the “Goldilocks” planet HD 85512b, which is about 36 light-years away, might look like.