Dark matter particles may be heavyweights after all

• 18:30 29 November 2011 by Lisa Grossman

Dark matter is slowly running out of places to hide. Two new looks at the gamma-ray sky suggest that if the mysterious matter is a particle, it is heavier than 40 gigaelectronvolts, about 44 times the mass of a proton.

That contradicts hints from three experiments on Earth that pointed to a lightweight dark matter particle weighing just a quarter as much, although some researchers say such featherweights are still in the running.

Dark matter makes up about 80 per cent of the matter in the universe, but no one is sure what it's made of.

MORE: http://www.newscientist.com/article/dn21227-dark-matter-particles-may-be-heavyweights-after-all.html

gaw

Glenn A. Walsh, Project Director,
Friends of the Zeiss < http://friendsofthezeiss.org >
Electronic Mail - < gawalsh@planetarium.cc >
SPACE & SCIENCE NEWS, ASTRONOMICAL CALENDAR:
  < http://buhlplanetarium.tripod.com/#news >
Twitter: < http://twitter.com/spacewatchtower >
Facebook: < http://www.facebook.com/pages/SpaceWatchtower/238017839577841?sk=wall >
Blog: < http://spacewatchtower.blogspot.com/ >
Author of History Web Sites on the Internet --
* Buhl Planetarium, Pittsburgh:
  < http://www.planetarium.cc >
* Adler Planetarium, Chicago:
  < http://adlerplanetarium.tripod.com >
* Astronomer, Educator, Optician John A. Brashear:
  < http://johnbrashear.tripod.com >
* Andrew Carnegie & Carnegie Libraries:
  < http://www.andrewcarnegie.cc >
* Civil War Museum of Andrew Carnegie Free Library:
  < http://garespypost.tripod.com >
* Duquesne Incline cable-car railway, Pittsburgh:
  < http://inclinedplane.tripod.com >
* Public Transit:
  < http://andrewcarnegie2.tripod.com/transit >