These planets are likely to be rocky like Earth, and not gas giants or ice worlds. They get about the same heat from their star as we get from the sun, according to the latest results from NASA's planet hunting Kepler telescope. But don't book your flights yet. They may be close to Earth in size and likely temperature in the gargantuan scale of the universe, but they aren't quite close enough for comfort. Consider two of the new planets, the nearest to Earth discovered to date. If they have atmospheres similar to Earth's — a big if — one would be a toasty 140 some degrees and the other would hover around zero, said study lead author Guillermo Torres, an astronomer at the Harvard-Smithsonian Center for Astrophysics.