When you fly by at a million miles an hour, it can turn some heads—which is just what happened with this runaway star. Snappily named J1249+36, it’s going fast enough to break free of our galaxy’s gravitational pull and launch into intergalactic space, Newsweek reports. The question is what kicked J1249+36 so hard that it’s flying 3 times faster than the sun and 1,500 times faster than sound. Space.com mulls one theory, that J1249+36 once played binary companion to a “dead” white dwarf—a former sun-like star that exhausted its hydrogen supply but, in this case, fed off its mate and sucked up mass until it exploded (see video).
The hope now is to unpack the star’s elemental composition and see if it was “polluted” by a white dwarf explosion, or originated in a globular cluster likely to host black holes. Such “hypervelocity” stars aren’t that rare—an old Smithsonian article estimates roughly 1,000 are zooming around our galaxy—but this story contains two other nice tidbits: J1249+36 belongs to a class of the galaxy’s most ancient stars called subdwarfs, per Science Daily, and volunteer scientists who stumbled on it were combing through data for evidence of the mysterious “Planet 9.” (Planet 9 might not be a planet.)
Daisy Hips is a science communicator who brings the wonders of the natural world to readers. Her articles explore breakthroughs in various scientific disciplines, from space exploration to environmental conservation. Daisy is also an advocate for science education and enjoys stargazing in her spare time.
