Feb 15 1977
From The Space Library
A project known as DUMAND (deep underwater muon and neutrino detection) would use a large area of the Pacific Ocean near Hawaii to detect the arrival of extremely high-energy particles from space, Walter Sullivan reported in the NY Times.
Neutrinos, considered the clues to several astronomical mysteries, had been hard to detect because of their lack of mass or electrical charge; moving at the speed of light, they apparently could pass entirely through the earth with no trace. A new science, neutrino astronomy, would use an array of microphones laid out on the sea bottom northeast of the island of Maui, in an area shown to be "pool-table flat" by survey ships from the Hawaiian Inst. of Geophysics, to listen for sound impulses generated by high-energy neutrinos colliding with atoms in the sea water. Collision would produce particle showers that should generate sound pulses as well as flashes of light known as Cerenkov radiation, resulting from the passage of particles through the water at speeds faster than the speed at which light proceeds through water. The original plan would have recorded the flashes to detect particles ejected by stellar explosions (supernovas); Soviet scientists had offered the use of 10 000 photodetectors for the experiment.
The first stage of the project would probably use acoustic detection, however, because of its greater sensitivity and economy: sound waves would travel through water far more efficiently than light would, the report said, and the project could use microphones spaced as far apart as 900meters in an array measuring 10km2, linked by a 56km undersea cable carrying data to a laboratory on Maui and supplying electrical power to the detectors. Recording the precise arrival time of a pulse at each detector would indicate the direction from which the neutrino came. As the neutrinos' paths (unlike those of other particles) would not be bent by magnetic fields in space, the way in which they had come would point to the source, first clue to cosmic ray origins. The high-energy particles and the muons produced when they hit the atmosphere were among the most energetic radiation known. (NYT, Feb 15/77, 14)
Telesat Canada expected to award contracts in Nov. 1977 for three commercial telecommunications satellites, the Wall Street Journal reported. The new comsats would use higher frequency bands than the three Telesat Canada satellites now providing television, telephone, and message communications throughout Canada. First of the high frequency comsats would be delivered early in 1980 and launched later that yr. (WSJ, Feb 15/77, 3)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
