spacetoday.net: Gas cloud to collide with Milky Way

Gas cloud to collide with Milky Way

Posted: Tue, Jan 15, 2008, 7:38 AM ET (1238 GMT)
Smith's Cloud approaching Milky Way (NRAO)

A massive cloud of gas is on a collision course with the Milky Way galaxy and will trigger a new round of star formation when it arrives, astronomers reported last week. The cloud, called Smith's Cloud, is 11,000 light-years long and 2,500 light-years wide, and is on a path that will collide with our galaxy in 20 to 40 million years, according to research by NRAO astronomers. That collision will trigger a round of star formation, much of it supergiant stars that will live for only a few million years before going supernova. The region of the collision is about 90 degrees ahead of the Sun in the plane of the galaxy.