New Class of Hypervelocity Stars Discovered
Sometimes you just feel like getting away, but something holds you back. For stars what typically holds them back is the massive gravity of our galaxy, but some have been found escaping, thanks to a kick from the galactic core. New research from Vanderbilt University using data from the Sloan Digital Sky Survey however has identified some hypervelocity stars with a different story to them.
Generally for a star to escape the Milky Way, it needs to be traveling at least a million miles-per-hour fast than the motion of the galaxy. Previously identified hypervelocity stars likely acquired such a speed from the supermassive black hole at the center of our galaxy. The stars were probably part of a binary system that formed near the galactic core, and when their partner was grabbed by the black hole, they received the massive kick. These new stars however do not appear to be from the core or another exotic region of the galaxy, and are actually about the size of the Sun, which makes their possible origin quite confusing.
One important caveat to this research is that it could all be a fluke. Typically measuring a star's velocity takes decades of measurements, but the researchers do not have that much data. While that does mean it is possible the stars are not traveling that quickly, the researchers are confident at least some of them all, thanks to the statistical tests they ran.
Source: Vanderbilt University