For the first time in history, NASA astronomers have "discovered the first Earth-size planet outside the solar system that has a rocky composition like that of Earth." The technical name is Kepler-78b but they should call it just Hell. Earth's hellish twin.
While the planet has the same mass and size as our home planet, Kepler-78b is the first to have both a measured mass and size. It also has the same composition—rock and iron—and density of Earth, and rotates around a star that is "slightly smaller and less massive than the sun."
Sounds great, right? Sadly, this twin Earth located at 400-light-years from us in the constellation Cygnus is not the virgin paradise you are imagining. It is a blazing inferno, spinning around its sun every 8.5 hours. No way to live here. Just suffer for a second before burning.
The finding has been independently confirmed by other terrestrial telescopes and will be announced in Nature.
Artist rendering of Kepler-78b