Meet 'mega-Earth,' a souped-up, all-solid planet that, according to theory, should not exist.
With billions of stars in our galaxy alone, many with their own Earth-like planets, how are we to know which ones might be habitable? Well, new research thinks we might just have the clue, and it all has to do with purple bacteria.
NASA's Kepler telescope was launched to find other planets just like Earth -- and now, scientists think they may have found not just one, but three! Trace
According to Kepler data, the nearest 'Earth-like' exoplanet may be within 13 light-years from Earth.