What are quasar and pulsar

What is the difference between a pulsar and a quasar?

Pulsars are often referred to as cosmic beacons because they emit regularly recurring pulses - just like a beacon that flashes every few seconds. This analogy is actually quite accurate, since it is assumed that pulsars are rapidly rotating neutron stars that only emit their light in a narrow cone of light. There are also so-called X-ray pulsars, in which it is assumed that, in addition to the neutron star, there must also be a normal star in the system from which matter flows onto the neutron star. Quasars, on the other hand, are objects that appear almost star-shaped in the visible range of light, but emit enormous amounts of energy in other wavelength ranges. Hence the name quasar for Quasi-stellar object or Quasi-Stellar Radio Source. Today it is assumed that quasars are very far away from us and represent the brightest objects in space. Observing quasars closer to us led to a theory that could explain what these objects are actually about: the nuclei of active galaxies. In the case of distant quasars, the associated galaxies can no longer be recognized. A quasar, according to the current model, consists of a huge black hole into which matter falls. It does this in a disc-shaped structure, the so-called accretion disc. The radiation that we receive from the quasar comes from this extremely hot region. (March 15, 2001)

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