Galaxy May Be Full of 'Second Earths'

Astronomers looked at date from NASA's Kepler space telescope in orbit, and conclude that 6% of the red dwarf stars in the Milky Way probably have Earth-Like, habitable planets. They go one to say how red dwarfs stars are very common and they make up three out of four starts in our part of galaxy. The closest one could be  13 light-years away. For reference  a light year is 6 trillion miles but a lot closer than most yellow stars like Earth. "We thought we would have to search vast distances to find an Earth-like planet. Now we realize another Earth is probably in our own backyard, waiting to be spotted," said Courtney Dressing. Red dwarfs are older, smaller and dimmer than our sun, but a planet orbiting close to one could be sufficiently warmed to have liquid water. Dressing and her colleagues cited three possible planets that were spotted by Kepler, which was launched in 2009. One is 90 percent as large as Earth, and orbits its red sun in just 20 of our days. There is no saying what such a world would actually be like; the Kepler probe can only show whether distant stars have objects periodically passing in front of them. But based on that, scientists can do some math and estimate the mass and orbit of these possible planets. So far, Kepler has spotted more than 2,700 of them in the small patch of sky it has been watching

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