Neutron Stars

The following citations listed in this article are from What is a neutron star? | Astronomy Essentials | EarthSky.

    Neutron stars are these bizarre cores of dead stars that are left over after supernovae explosions. They are created when the supernova's core collapses on itself. Neutron stars have similar masses to our Sun, with about 40% more. Like lots of stars, these stars are extremely dense, with a single tablespoon weighing over 1 billion tons! That's the same weight as 125,000 Asian elephants. Altogether, one of these stars can weigh more than Mount Everest, which is the tallest mountain above sea level. 

Image Credits: Most massive neutron star ever measured stretches the limits of physics

    Neutron stars appear pale blue; in addition, they are extremely hot, measuring in at 600,000 degrees Celsius. In the image above, you can see faint spiral arms forming around the core of the star. This is actually quite unusual, but not impossible. However, the core of a neutron star usually produces a major luminous light, like in the image above. These stars are often looked over and are not spoken about as often as other phases of a star, like supernovae or Red Giants.