M31 The Andromeda Galaxy
Andromeda is the largest galaxy in waht astronomers call the Local Group, which includes the Milky Way, the Triangulum Galaxy, and dozens of smaller dwarf and irregular galaxies. The Andromeda galaxy was first observed by Persian astronomers, thousands of years ago, and was later cataloged by Charles Messier in 1764. He classified it as M31. In 1912, astronomers calculated its speed to be 300 kilometers per second, moving towards our solar system. Recent estimates have calculated that Andromeda Galaxy is about 220,000 light-years in diameter, twice the estimate diameter of the Milky Way. While other galaxies are moving away from us, Andromeda is on a collision course with the Milky Way. Our two galaxies will collide with one another in about 2.5 billion years, and begin forming a giant, ball shaped elliptical galaxy. On student star gazes, the core of the brightly lit Andromeda Galaxy is very easy to see with your telescopes. This picture was taken the night of October 23rd a mild clear night