National Geographic News, Reporting Your World Daily

Thursday, October 28, 2010

Photo: Dark Matter Proof Found Over Antarctica?


Email to a Friend	<< Back to Full Story

The so-called bullet cluster, formed by the collision of two large galaxy clusters, offered astronomers the first direct proof of the gravitational effects of dark matter in 2006.

In November 2008 scientists announced an unexpected number of high-energy electrons over Antarctica that matches the signal expected from the destruction of dark matter. But team members say they are also considering another explanation: The electrons come from a nearby but mysterious object that is bombarding Earth with cosmic rays.

X-ray image courtesy NASA/CXC/CfA/M.Markevitch et al.; optical image courtesy: NASA/STScI; Magellan/U.Arizona/D.Clowe et al.; lensing map courtesy NASA/STScI; ESO WFI; Magellan/U.Arizona/D.Clowe et al.