The Stars of the Orion Arm
We are now about 2000 light years from Earth, and are nearing the edge of the disk of our galaxy. The Sun orbits the center of the Milky Way galaxy at a distance of about 30 000 light years. The galaxy is about 3000 light years thick at the Sun's position. We are getting ready to exit the plane of our galaxy. The Milky Way contains between 1011 and 1012 stars, an average sized spiral galaxy.
Copyright © 2016 by Bruce Bryson