National Geographic News, Reporting Your World Daily

Thursday, October 28, 2010

Photo: Particles Larger Than Galaxies Fill the Universe?


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Every day billions of subatomic particles called neutrinos are streaming at Earth from the sun. But these particles have no charge, very tiny masses, and move near the speed of light, making them especially hard to detect (above, a diver services a tank of water in Michigan used to detect neutrinos).

In May 2009 astronomers trying to measure neutrino masses found that the oldest known neutrinos might have been stretched by the expansion of the universe so that each particle encompasses a space larger than thousands of galaxies.

Photograph by Joe Stancampiano/NGS