Publisher's note: I am always fascinated by the cosmos, and this story of stars actually escaping the gravitational pull of our galaxy is amazing.
Science Daily: Jan. 9, 2014 — An international team of astronomers has discovered a surprising new class of "hypervelocity stars" -- solitary stars moving fast enough to escape the gravitational grasp of the Milky Way galaxy.
The discovery of this new set of "hypervelocity" stars was described at the annual meeting of the American Astronomical Society this week in Washington, D.C., and is published in the Jan. 1 issue of the Astrophysical Journal.
"These new hypervelocity stars are very different from the ones that have been discovered previously," said Vanderbilt University graduate student Lauren Palladino, lead author on the study. "The original hypervelocity stars are large blue stars and appear to have originated from the galactic center. Our new stars are relatively small -- about the size of the sun -- and the surprising part is that none of them appear to come from the galactic core."
The discovery came as Palladino, working under the supervision of Kelly Holley-Bockelmann, assistant professor of astronomy at Vanderbilt was mapping the Milky Way by calculating the orbits of Sun-like stars in the Sloan Digital Sky Survey, a massive census of the stars and galaxies in a region covering nearly one quarter of the sky.