Scientists discover 'super-Earth'
Astronomers have found a planet very similar to ours that is 9,000 light years away from the Sun
Lewis Smith
Times Online
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Astronomers hunting for planets have found one with the mass of Neptune 9,000 light years away from our Sun. They believe it is similar in composition to Earth.
Initial analysis suggests that, like Earth, it has a rocky core, though at minus 184C (-300F) its surface is covered with ice rather than water. The discovery, using a new technique called gravitational microlensing, has forced scientists to revise their estimates of how many Earth-type planets exist.
Microlensing is also opening up the prospects of finding another planet of the same type and mass as Earth, regarded as the holy grail of astronomers, because it is such a sensitive method. Andrew Gould, professor of astronomy at Ohio State University, said that the discovery, reported in Astrophysical Journal Letters, was exciting.
“It appears to be a terrestrial planet of rock and ice. The implication is that these icy super-Earths are pretty common.” It is the first time that such a planet has been found occupying the same region of a solar system as the gas giants Jupiter and Saturn do in ours. Astronomers were able to find the planet, one of the coldest yet discovered outside our solar system, by taking readings during gravitational microlensing in the galaxy.
Mar 14, 2006
Astronomers have found a planet very similar to ours that is 9,000 light years away from the Sun
Lewis Smith
Times Online
_________
Astronomers hunting for planets have found one with the mass of Neptune 9,000 light years away from our Sun. They believe it is similar in composition to Earth.
Initial analysis suggests that, like Earth, it has a rocky core, though at minus 184C (-300F) its surface is covered with ice rather than water. The discovery, using a new technique called gravitational microlensing, has forced scientists to revise their estimates of how many Earth-type planets exist.
Microlensing is also opening up the prospects of finding another planet of the same type and mass as Earth, regarded as the holy grail of astronomers, because it is such a sensitive method. Andrew Gould, professor of astronomy at Ohio State University, said that the discovery, reported in Astrophysical Journal Letters, was exciting.
“It appears to be a terrestrial planet of rock and ice. The implication is that these icy super-Earths are pretty common.” It is the first time that such a planet has been found occupying the same region of a solar system as the gas giants Jupiter and Saturn do in ours. Astronomers were able to find the planet, one of the coldest yet discovered outside our solar system, by taking readings during gravitational microlensing in the galaxy.
Mar 14, 2006
