Piece of Missing Cosmic Matter Found

[mickw]

Astronomers have found a piece of the universe's puzzle that's been missing for awhile: a type of extremely hot, dense matter that is all but invisible to us.
Engaging in something like cosmic accounting, astronomers have tried to balance the scant amount of matter that has been directly observed with the vast amount that remains unobserved directly. The latter constitutes about 90 percent of the universe's matter.

More:  http://www.space.com/scienceastronomy/080512-mm-matter-found.html