pulsar(redirected from pulsare)
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Any of several celestial objects emitting periodic, short, intense bursts of radio, x-ray, or visible electromagnetic radiation, generally believed to be quickly rotating neutron stars.
[From puls(ating st)ar (influenced by quasar).]
(Astronomy) any of a number of very small extremely dense objects first observed in 1967, which rotate very rapidly and emit very regular pulses of polarized radiation, esp radio waves. They are thought to be neutron stars formed following supernova explosions
[C20: from puls(ating st)ar, on the model of quasar]
any of several hundred known celestial objects, generally believed to be rapidly rotating neutron stars, that emit pulses of radiation, esp. radio waves, with a high degree of regularity.
[1968; puls(ating st)ar, on the model of quasar]
A spinning neutron star that emits radiation, usually radio waves, in very short and very regular pulses. Because a pulsar's magnetic poles do not align with the poles of its axis, its beams of radiation sweep around like the beacon of a lighthouse.
Did You Know? When a very large star goes off like a giant bomb in an explosion called a supernova, the core of the star collapses into either a neutron star or a black hole. In 1054, one of these explosions could be seen in the sky during both day and night for 23 days. Chinese astronomers took note of this "guest star," and rock paintings and pottery found in Arizona and New Mexico suggest that Native Americans recorded it, too. In the 18th century, astronomers discovered in the constellation Taurus the leftovers that had been blown away by this explosion, the bright cloud called the Crab Nebula. In the late 1960s, 900 years after the supernova, astronomers found a source of rapidly pulsing radio waves, with 30 flashes per second, near the center of this nebula. The source of this pulsating radiation is an object that was named a pulsar. We now know that a pulsar is a rapidly rotating neutron star whose radiation is emitted like a spinning flashlight. Over 700 pulsars have now been detected, with rates of rotation ranging from once every 4 seconds to more than 600 times per second.
A rapidly rotating neutron star that gives off regular bursts of radio waves.