Pulsars | Earth, Solar System and Universe.

Pulsars are sources of radio waves that vibrate with regular periods. They are detected by radio telescopes.
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The Pulsar Word is an acronym for "pulsating radio source", pulsating radio source. Required clocks extraordinary accuracy to detect changes of pace, and only in some cases.
Studies indicate that a pulsar is a small neutron star spinning at high speed. The best known is the Crab Nebula. Its density is so great that, in them, the subject matter of the extent of a ball pen has a mass of about 100,000 tons. They emit a large amount of energy.
Magnetic field, very intense, is concentrated in a small area. This accelerates it and makes it to emit a beam of radiation that we receive here, as radio waves through telescopes.
Pulsars were discovered in 1967 by Jocelyn Bell and Anthony Hewish in the Observatory's radio astronomy in Cambridge. Many pulsating stars are known, but only two, the press of the crab, and the press of sail, emit detectable visible pulses. It is known that these two also emit pulses of gamma rays, and one, the crab, also emits pulses of X-rays.
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The regularity of pulses is phenomenal: observers can now predict the times of arrival of pulses in advance of a year, with a precision better than a millisecond.
The buttons are strongly magnetized neutron stars. The rapid rotation, therefore, makes them powerful generators, capable of accelerating charged particles to energies of millions of volts billion.
These charged particles are responsible for the beam of radiation in radio, light, X-rays, and gamma rays. Its power comes from the rotation of the star, which has therefore to be lowering speed. This decrease in speed can be detected as a lengthening of the period of pulses.

Where are pulsars?

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Pulsars have been found mainly in the milky way. A full count is impossible, since you pulsars weak only can be detected if you are close.
Radio polls have already covered almost the entire sky. Their distances can be measured from a delay in the time of arrival of pulses observed in the radio frequencies; the delay depends on the density of electrons in the interstellar gas, and distance traveled.
Extrapolating from this small sample of pulsars detectable, it is estimated that there are at least 200,000 pulsars in our galaxy. Whereas those pulsars whose beams Lighthouse not sweep in our direction, the total population should reach one million.
Each pulsar emits for about four million years; After this time you have lost so much rotational energy that can not produce detectable radio pulses. If we know the total population (1,000,000), and life (4,000,000 years), we can deduce that a new strike should be born every four years, assuming that the population remains stable.
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Recently found pulsars in a globular cluster. It is thought that they had been trained there by the accretion of matter in the white dwarf stars that are part of binary systems.
Other pulsars are born in supernova explosions. If all pulsars them were born in supernova explosions, we could predict that there should be a supernova in our Galaxy every four years, but this is not yet clear.

Translation for educational purposes authorized by: Astronomía: Tierra, Sistema Solar y Universo

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