We know that the Milky Way is surrounded by an array of satellite galaxies, the largest of which is the rather aptly named Large Magellanic Cloud. But figuring out exactly how far away our cosmic neighbor is has proved fiendishly difficult.
There's an old fringe theory that the Sun isn't our system's only star, that a red dwarf star named Nemesis is hiding out in the Oort Cloud. We've never found any evidence for it or any other secret companion star, and if this simulation is any indication, that's very good news for the gas giants.
Back in September, NASA's planet-hunting satellite Kepler made one of its most dramatic discoveries when it spotted a planet orbiting two stars. But was this a one-of-a-kind cosmic freak, or are there lots of these strange planets? Now we know.
This is AB7, a binary star system found in one of the nearby Magellanic Cloud galaxies. The two stars are constantly venting massive amounts of stellar material. That process is heating up one of the stars to absolutely unimaginable temperatures.
Stars known as blue stragglers have pretty much discovered the cosmic equivalent of the fountain of youth - they should be old and nearly out of fuel, yet they continue to burn hot and bright blue like a young star.
Located just 4.3 light-years away, the Alpha Centauri star system is our closest neighbor. But theirs is a very different solar system, as it's home with not one, not two, but three stars. Here's the short guide to Alpha Centauri.
Astronomers believed that binary star systems were too volatile to support many planets, because the overlapping gravitational forces of the two stars would pull most planets apart. But one exoplanet 69 light-years away survives just fine...by orbiting the wrong way.