The stillness of the night sky is deceiving. Because of the sheer vastness of space, stars appear unmoving like celestial fixtures. In actuality, though, they're zipping through the cosmos - some at ridiculously high speeds: thousands, and even tens of thousands of kilometres per second.
That's roughly 100,000 times faster than the speediest train and 1,000 times faster than the fastest spacecraft that's ever flown. That's fast enough for a few spins around Earth in the time it takes to put on your socks. The point is, that's fast.
Some astrophysicists have suggested that, in principle, stars could go even faster - even as fast as light. Such stars may even harbour planets, prompting speculation that they could serve as intergalactic transport for alien life.
But you don't need to speculate to find stars rocketing out of our own Milky Way Galaxy. A speed of a thousand or so kilometres per second is already fast enough to send a star hurtling toward the lonesome expanse. These hypervelocity stars, as they're called, were only discovered about 10 years ago. So far, astronomers have found a total of about two dozen leaving the Milky Way. And they're trying to find more.
