Word: pulsars
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...Maran and Theodore Stecher ask archaeologists for help in determining the age of a giant celestial gas cloud. Known as the Gum Nebula, the cloud has been attracting more than usual attention among astronomers. At its center, some 1,500 light-years away from earth, they have discovered a pulsar -a neutron star that emits regularly spaced radio signals. What possible information could archaeologists offer? Quite a bit, the astronomers explain. Both the Gum Nebula and pulsar are remnants of a relatively rare heavenly event: a supernova, the cataclysmic explosion of a massive dying star. The astronomers point out that...
There are implications of the discovery that go beyond the white-dwarf theory. Since the discovery of pulsars three years ago, most astronomers have come to agree that the strange signal-emitting objects are in fact neutron stars-dying stars that according to theory have collapsed with such force that all that remains is a ball of neutrons as small as ten miles across. With the help of Kemp's new technique for detecting distant magnetism, astronomers may now be able to substantiate their pulsar theories. If pulsars are indeed neutron stars-objects even more dense than white dwarfs...
Most scientists believe that pulsars emit their pulses by spinning rapidly. The time between pulses has been believed to be constant, but Drake has found that it is increasing very slightly. The energy the pulsar loses in rotation is given off as radiation; the energy loss of a pulsar is 100,000 times the energy loss...
...electronic device that made 12,000 separate light-intensity measurements every second. They quickly discovered that the starlight increased to a peak about 30 times per second, a variation too rapid to be detected by the human eye. The flashes corresponded exactly to the radio pulses from the Crab pulsar, strongly suggesting that the target was indeed the pulsar. Unlike an earlier and apparently erroneous sighting of a flashing pulsar (TIME, May 31), this discovery was confirmed by the McDonald Observatory in Texas and Arizona's Kitt Peak National Observatory...
Astronomers do not yet know why the Crab pulsar flashes, but some suspect that its bursts of light are generated by charged particles in its intense magnetic field. Now that they have seen the light, scientists are attempting to take a clear spectrograph of the pulsar and to determine if the light itself is polarized. They are investigating a new report by astronomers at an observatory on Malta, who saw strange "ghost" flashes about 3° to either side of both the Crab pulsar and another nearby pulsar. With these new clues, scientists hope to be able to learn more...