Cygnus OB2 in 60 Seconds

Narrator (April Hobart, CXC): The Milky Way and other galaxies in the universe are home to many star clusters and associations that each contain hundreds to thousands of hot, massive, young stars. Astronomers would like to better understand how these star factories form and evolve over time. Cygnus OB2 is the closest massive star cluster to Earth, making it an excellent target for astronomers to study. A long observation from NASA's Chandra X-ray Observatory of Cygnus OB2 revealed about 1,700 X-ray sources. Scientists think that nearly 1,500 of these X-ray sources are young stars. The X-ray emission comes from the hot outer atmospheres of these stars ranging in age from one million to seven million years old. This makes the stars in Cygnus OB2 practically newborn babies when compared to a star like our Sun at about 5 billion years in age. By combining Chandra's data with those from other telescopes, a more complete story of star birth and early adolescence is made.