 Hubble has captured this image of a hypervelocity star over a quarter of a million light-years away. It's 200,000 light-years above the galactic plane and traveling at 722 km per second. That's 450 miles per second. That's fast enough to escape the galaxy's gravitational grip. Astronomers think it was a member of a multi-star system and was jettisoned by the black hole in our galaxy's central bulge. We'll cover black holes when we get to this segment on the Milky Way. The black hole's tremendous gravitational pull stripped one member while violently ejecting the other member deep into space at these high velocities conserving the system's momentum. The first example of hypervelocity star was discovered in 1995. This one, US 708, is a second such star to be discovered. It is an extremely rich helium hot white dwarf moving at 1,200 km per second. That's 746 miles per second. That makes it the fastest star ever discovered. It crossed the galactic plane around 14 million years ago and is thought to be the companion of an exploding star that sent it out into intergalactic space.