The odds are that you've never heard of a particle called the neutralino. But if one model of the universe is right, it makes up most of the matter in the universe -- the mysterious dark matter.
Although we can't see it, astronomers know that dark matter is there because its gravity pulls on the stars and galaxies that we can see. It probably consists of elementary particles.
One way to detect the dark matter is with a particle accelerator, as University of Texas physicist Steven Weinberg explains:
WEINBERG: And there is a very large elementary particle accelerator which is just now going into action in Europe, the Large Hadron Collider, in which two protons collide with each other head-on, and one looks for the products of the proton-proton collision. Now lots of junk is produced. It's like the proverbial needle in the haystack to find the occasional dark matter particle that might be produced. Our cosmological theory is good enough so that if the Large Hadron Collider finds a new particle that might be the dark matter, by measuring its properties, we'll be able to confirm that it either is or is not the dark matter.
But other models say that the dark matter particle is something that can't be made in accelerators. If that's the case, then the true nature of dark matter may remain a mystery for a long time to come.
Script by Damond Benningfield, Copyright 2010