Researchers are baffled as to what sent them soaring
Something catapulted a pair of stars from the outer rim of our galaxy, but astronomers aren’t sure what. A binary star known as PB 3877 is rocketing away at about 2 million kilometers per hour — possibly fast enough to escape the galaxy’s gravitational pull — and all the usual explanations for such speedy stars fall short. Astrophysicist Péter Németh of the University of Erlangen-Nuremberg in Germany and colleagues report the discovery in the April 10 Astrophysical Journal Letters.
Many galactic escapees get kicked out after a close brush with the supermassive black hole in the Milky Way’s center. But PB 3877, first noticed in 2011 and currently about 18,000 light-years away in the constellation Coma Berenices, has been nowhere near that behemoth. A supernova could be responsible; it has happened before (