Neutron stars are stellar objects born out of the explosion or death of other larger stars. These are compact stars which are known for its densest and smallest structure among the stars known to humans. By radius they are about 11 – 11.5 Kilometers or 7 miles, yet their mass is as twice as that of the Sun’s.
Some huge stars (almost four to eight times the size of the Sun), dies by exploding into supernova. These stars, after their explosion, leave their outer layer into the space, but the core remains. The core, however, do not produces nuclear fusion. Hence, a neutron star demonstrates one of the possible ends of a star. Though they are dying, the four known (known to humans) neutron stars do possess their own planets. It is estimated that there are around 100 million neutron stars in the Milky Way. This estimate is from the counts of supernova, yet many of these neutron stars are believed to be cold and less active.
A neutron star rotates. The power that given by the supernova makes the neutron stars rotate. As years pass, these compact stars shrink and the speed of rotation increases. The rotating neutron stars are widely known as pulsars. Some of these pulsars spin at 716 rotations per second. Are they not amusing? There is more… a teaspoon full of neutron star material is expected to weigh up to 10 million tons.