NASA’s Kepler space telescope is busted and it may never work normally again. But during its four years of exemplary service, the planet-hunting telescope provided astronomers with an unprecedented glimpse into the Milky Way. Here are the most incredible discoveries made by Kepler.

After four years of service, NASA’s planet-hunting Kepler telescope has suffered a second serious malfunction — one that threatens to permanently end the mission. Controllers on the ground can no longer control its orientation. It looks bad, but NASA isn’t giving up hope.

Good grief, it's gorgeous. The New York Times just unveiled the slickest exoplanet animation/infographic we've laid eyes on. Go check it out. Now.

NASA's Kepler mission has discovered a trio of distant planets that look remarkably like our own. Belonging to solar systems located 1,200 and 2,700 light years from Earth, the three Earth-sized worlds have been spotted orbiting in the so-called Goldilocks Zone of their parent stars – the "just-right" range at which…

In death, it has been said, there is often life. And while it may sound counterintuitive, this old saw may hold especially true in the search for life of the extraterrestrial variety. NASA's Kepler mission may be just years away from discovering Earth 2.0, but the first signs of life probably won't come from planets…

Current estimates put the number of stars in the Milky Way at well over 100 billion, each of which is thought to have at least one planet in its orbit. Assuming at least some of these planets have given rise to intelligent life capable of communicating with Earth, why haven't we heard from them yet?

Caltech astronomer John Johnson, co-author of a newly published study on the formation of planetary systems, calls the distribution of planets in our galaxy "mind-boggling." His team's are the latest in a string of predictions that pin the number of planets in the Milky Way at upwards of 100-billion. And these are…

Remember 55 Cancri e? Sure you do — and if you don't, you should. After all, it may be the first diamond planet ever discovered that orbits a Sun-like star. At least we think it is; if there's one thing 55 Cancri e is good at, it's fooling astronomers into thinking it's something that it's not.

Last September, NASA's planet-hunting Kepler mission announced the discovery of Kepler-16b, a "circumbinary" planet which, like Star Wars' Tatooine, orbits not one, but two stars.

There are 2,299 exoplanets featured in the video up top, all of which have been discovered by NASA's Kepler spacecraft since 2009.