View Full Version : Where’s M31

2010-Oct-27, 05:10 PM
Within our own galaxy, the thick disc is a distinct population of stars that resides above and below the main (thin) disc. Its stars have a larger range of velocities, are generally older and more metal poor. While astronomers aren’t entirely sure how it formed (remnants of accretion of small galaxies or ejection from the [...]

More... (http://www.universetoday.com/76713/wheres-m31s-thick-disc/)