Developments to Watch
`TAKING AN X-RAY PICTURE OF OUR UNIVERSE'
Subatomic particles called neutrinos come from inside such violent environments in space as black holes, quasars, and pulsars. Now, these rare, minute particles could open a window into the great beyond. That's because physicist Francis L. Halzen of the University of Wisconsin in Madison has found a way to chart neutrinos that "will be like taking an X-ray picture of our universe."
In one of three international experiments on neutrino detection, Halzen's team and one from the University of California hope to turn the South Pole into a telescope by lowering radiation detectors 800 meters into the ice. Since ice has no natural radiation, it serves as a better backdrop than water or soil. The earth will help filter out other radiation, which unlike massless neutrinos, can't pass through its core. Occasionally a neutrino will collide with an atom inside the earth and turn into a muon, a garden-variety form of radiation. The muon will leave a trace of light on the detectors--which are calibrated in billionths of a second to reveal the path and direction of the neutrino turned muon. Scientists hope to cover a square kilometer with detectors.EDITED BY PAMELA J. BLACK