FROM OUR Small is Beautiful file:
Astronomers say they may have discovered where the "missing mass" that appears to pervade the universe lies hidden.
The culprit: an elusive subatomic particle called the neutrino, or "little neutral one."
Neutrinos have no electric charge, travel at nearly the speed of light and are so insubstantial that billions of them could pass through the Earth without disturbing a single atom.
Neutrinos were long thought to have no mass at all. But recent experiments suggest otherwise.
Many theorists now suspect the neutrino does indeed have a teeny-tiny mass of its own -- about 500,000 times smaller than the mass of an electron, the lightest "normal" subatomic particle.
That's not much. But if there were enough of them they could account for the effects that lead scientists to believe visible matter like stars and planets make up no more than 10 percent of the total mass of the universe.
So how many neutrinos would it take to balance things out?
Sorry, we don't have enough space on this page for all the zeros it would take to print that number.
Suffice it to say the Creator undoubtedly had a good reason for fashioning a universe that is 90 percent invisible little puffs of cosmic nothingness.
Now all scientists have to do is figure out what it was.