Question

After they completely run out of fuel, all stars leave behind one of three objects, which do not usually do any more nuclear fusion. What are these three objects? Give the name of each and quick description.

Answer 1

All the stars leave behind three different objects, once they run out of fuel. These objects are i) White dwarf ii) Neutron star iii) Black hole.

Stars are compressed by gravitational attraction, But as the temperature increases nuclear fusion starts which is the primary reason for the brightness of star. Depending upon the initial mass of the star stars evolve in to one of the above three objects. If their mass is less than ( is mass of sun) , they form white dwarfs.

When their mass is more than but less than to , they form nertron stars.

If their initial mass is more than to , they form black holes.

In case of black holes, gravitational attraction overcomes the degeneracy pressure which arises due to Pauli's exclusion principle. Even light also cannot escape the gravitational attraction of black holes hence their name.

In case of neutron star, gravitational attraction is balanced by the degeneracy pressure of neutrons. These neutron stars are exptremely dense , very small objects. They give rise to X-ray and gamma ray radiation.Hence these stars also called pulsars.

In case of white dwarfs, are stars which have lost their outer layers in explosions called supernova.