Answer to Question #164189 in Astronomy | Astrophysics for Syed Abdullah Gilani

Question

Radio telescopes are an essential tool for modern astrophysics. They played a crucial role in discovering a fascinating astronomical object: Pulsars - highly compact objects that periodically emit radiation. Pulsars are still an active part of astrophysical research. Explain how pulsars are formed and the causes for their pulsating behaviour.

Answer 1

The pulsar is formed when the star more massive than the Sun (more than eight mass of the Sun) runs out of fuel in its core and collapses in on itself. This results in massive explosion called supernova. Since there is no opposing force of fusion to balance the gravitational force, the gravity begins to pull the mass of the star inward until it implodes. The gravity compacts the mass of the star and, as a result, pulsar composed primarily of neutrons packed so tightly that they no longer exist as normal matter. That's why the pulsars often called the neutron stars. Pulsars spin hundreds of times per second. They spin so fast due to the law of conservation of angular momentum (the stars from which they formed also rotates and bringing the mass closer to the center of the neutron star increases its rotation speed). The pulsars radiate two steady, narrow beams of light in opposite directions. The pulsars appears to flicker because of their spin: as the pulsar rotates, the beam of light may sweep across the Earth, then swing out of view, then swing back around again.