There should be more matter in the universe that anyone could see. All the galaxies and the stars weren't weighty enough to explain why the universe is expanding the way it is. Now they say the little neutrino, which they thought didn't weigh at all, has mass. Because there are so many of them, if they have even a tiny mass, then they can influence the future expansion of our universe and tell us about whether our universe will continue to expand forever, whether our universe eventually will collapse back in on itself. Neutrinos are subatomic particles that come from nuclear reactions inside stars, or when cosmic rays collide with our atmosphere.
Trillions pass through the Earth everyday undetected.
Scientists working at in underground observatory near Tokyo, Japan were the first to make the discovery, that the tiny neutrino isn't just a flash of energy as previously thought, but has mass. In fact these elusive neutrinos could account for most, if not all of the dark matters in the universe. That's material scientists think is out there, but has never been seen. For our understanding of the universe, we know there are a lot of neutrinos around today, and if they have a tiny bit of mass, as indicated by this experiment, then they account for a significant fraction of the matter in the universe and may explain the dark matter. Scientists at other neutrino observe tories around the world will work to verify the claims and change scientists' thinking about the fundamental nature of matter.