They're invisible. They whiz around at the speed of light. And they're flying through you right now!
Today, hundreds of scientists around the world are probing the secrets of elusive subatomic particles called neutrinos. But it's hard to study particles with no charge or weight that you can't even see. So researchers at the Fermi National Accelerator Laboratory are creating neutrinos and beaming them through the Earth, to a detector four hundred and fifty miles away. That trip, from Illinois to Minnesota, takes a neutrino only one four-hundreth of a second. Out of trillions of neutrinos that make the trip each year, only about fifteen hundred end up colliding with particles in the detector in Minnesota. During their trip, some may change into different kinds of neutrinos. Deborah Harris, a physicist at Fermi, describes the transformation.
"It's really a weird phenomenon. Instead of head and tails, it's like you flip a quarter and a dime lands instead -- I mean it's really, really different."
(SOUND: coin landing on surface)
The colliding neutrinos send out detectable signals indicating what type of neutrino they've become. Because neutrinos result from both fission and fusion, lots of them originate within the sun. Eventually, they may help explain the evolution of the sun, along with the origins of atoms -- the building blocks of the universe. I'm Eric Phillips.
"Imagine That!" covers projects funded by the U.S. government's National Science Foundation. Federally-sponsored research -- brought to you by you! Learn more at www.nsf.gov.