Word: pulsare
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...colleagues, Peter M. McCulloch and Lee A. Fowler, was a triumph of radio astronomy. In 1974, while scanning the heavens with the giant bowl-shaped radio telescope near Arecibo, Puerto Rico, the researchers detected rhythmic radio signals from the constellation Aquila. The bursts were coming from a pulsar, or rapidly rotating neutron star-the incredibly compressed cadaver of a giant star whose nuclear fires have died out. Some 15,000 light-years away, it apparently was in orbit around a second compact object, perhaps another neutron star or even a black hole, whose gravity is so strong that nothing...
...next development in watches, a few Christmases hence, will be the nuclear timepiece, powered by a radioactive cell that will last 50 years. Until then, Pulsar, a pioneer digital manufacturer, has decided to more than make do with existing technology. It has put together what it calls the "personal information center"-a digital watch combined with a miniaturized calculator that enables the wearer to add, subtract, divide and multiply. It can calculate figures up to 999 billion, and has a memory bank. Pulsar will manufacture only a limited number of the solid-gold, 22-key calculator watches...
Radio Beacon. Further observations by Hewish and other radio astronomers soon put this tantalizing speculation to rest but eventually confirmed that a pulsar is a neutron star. Space, in fact, seems to be full of neutron stars. Since Hewish and his assistant, Jocelyn Bell, found the first one, about 100 more have been identified by astronomers. A neutron star is a bizarre object. It is formed when a giant star exhausts its nuclear fuel and collapses inward on itself, crushing much of its matter into a ball of neutrons some ten miles in diameter-but so dense that a thimbleful...
Billed as "science adventures for curious grownups," Nova so far has looked to the skies to describe the distant Crab nebula and explain the pulsar, a kind of astronomical time clock that lies within it. The program has gone underseas for a scientific examination of dolphins and whales, resisting the temptation to Flipperize its subjects. It has even presented a fascinating inside look at the difficulties that a team of science-film makers encountered in making a nature film. Other shows will explain experiments with Washoe, a chimpanzee who has been taught to speak in sign language, and tackle...
...that they have located a black hole. Its presence was hinted at in 1971 by the first earth-orbiting X-ray satellite Uhuru, which detected a strong and widely fluctuating flow of X rays from Cygnus. Scientists suspected that the radiation source, which they named Cygnus Xl, was a pulsar, or neutron star, the result of a different form of stellar collapse. But the uneven fluctuations bore no resemblance to the steady bursts of radiation from other pulsars...