Take that, Andromeda!

Fasten your seat belts — we’re faster, heavier, and more likely to collide than we thought. Astronomers making high-precision measurements of the Milky Way say our galaxy is rotating about 100,000 miles per hour faster than previously understood.

Photo: (Click on thumbnail for fullsize image.) Detail from “Approaching the Milky Way” by Jon Lomburg. (SETI League photo, used by permission.)

That increase in speed, according to Mark Reid of the Harvard-Smithsonian Center for Astrophysics, increases the Milky Way’s mass by 50 percent, bringing it even with the Andromeda Galaxy. “No longer will we think of the Milky Way as the little sister of the Andromeda Galaxy in our Local Group family,” Reid said.
The larger mass, in turn, means a greater gravitational pull that increases the likelihood of collisions with the Andromeda galaxy or smaller nearby galaxies.

Our solar system is about 28,000 light-years from the Milky Way’s center. At that distance, the new observations indicate, we’re moving at about 600,000 miles per hour in our galactic orbit, up from the previous estimate of 500,000 miles per hour.

Stephen Colbert of  Comedy Central’s “The Colbert Report” gloated over the findings in a segment broadcast earlier this year:

The Colbert Report Mon – Thurs 11:30pm / 10:30c
Little Victories – America’s Galaxy Is Big
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Posted: 27 July 2009
About the Author:

Christine Pulliam is a public affairs specialist at the Harvard-Smithsonian Center for Astrophysics, which is a joint collaboration between the Smithsonian Astrophysical Observatory and Harvard College Observatory located in Cambridge, Mass.