Astronomers have discovered a hypervelocity star blasting through the Milky Way at 540 km/s. These have been seen before, but what makes this special is a super-Neptune exoplanet in orbit around the star. It's possible that the star was part of a binary system that came too close to the black hole at the center of the Milky Way, which stripped away one of the pair, hurling the other away at high velocity. Amazingly, it hung onto its planet through the process.
https://www.nasa.gov/universe/nasa-scientists-spot-candidate-for-speediest-exoplanet-system/