Friday, January 9th, 2009

New Milky Way Measurements

Artist's conception of the Milky Way galaxy. Robert Hurt, IPAC; Mark Reid, CfA, NRAO/AUI/NSF

The Milky Way galaxy is bigger, heavier, and faster-spinning than researchers once thought. In work presented this week at the meeting of the American Astronomical Society, scientists reported that our home galaxy is rotating about 100,000 miles per hour faster than previously understood. The revised rotation speed also corrects estimates of the galaxy's mass, making our galaxy closer in mass to that of Andromeda, which was previously thought to be significantly bigger than the Milky Way.

On the down side, the larger mass estimates also mean that our galaxy is more likely to collide with other nearby galaxies due to increased gravitational pull. We'll take a look at the new vital stats of the Milky Way, and talk about what they mean to astronomers.