First direct evidence of dark matter

Two galaxies passed through eachother (or 'collided') and astronomers found that the bulk of normal matter was behind the galaxies, in the hot gas clouds which come from the 10 million mph collision.

However, the bulk of the mass of the galaxies was ahead of the clouds, closer to the galaxies, and by analyzing the gravitational lensing effect of this non-luminous mass they confirmed that it has way more mass than the ordinary matter in the cloud.

This is big news. Congratulations Douglas Clow, leader of the study. Pop him an email if you have questions or congratulations: dclowe@as.arizona.edu

The results are being published in an upcoming issue of The Astrophysical Journal Letters, but if you want to read more just Google it, plenty of sites have articles on it.