AMANDA
The South Pole is an inhospitable place to build and operate a
telescope. But crystal-clear ice is an excellent medium for
observing neutrinos as they pass through the Earth. Since 1999,
AMANDA, the Antarctic Muon And Neutrino Detector Array (seen here
during its assembly), has used the Antarctic ice to seek out
neutrinos. When the particles interact in the ice they can produce
muons, charged particles that are like electrons but heavier. The
muons create faint flashes of light as they pass through the ice
some 1.2 miles below the surface, where they are sensed by
AMANDA's hundreds of light-sensitive phototubes supported on 19
tethers frozen in the ice. AMANDA's goal is to conduct neutrino
astronomy, identifying and characterizing extra-solar sources of
neutrinos, which could provide important clues in the search for
dark matter.