Neutron Star
A neutron star results from the gravitational collapse of a massive star during a supernova event. Neutron stars are the densest and tiniest stars known to exist in the universe; typically having a diameter of about 10 km they have a mass of several times that of the Sun. Neutron stars probably appear white to the naked eye.
Neutron stars are the end points of stars whose mass after nuclear burning is greater than the Chandrasekhar limit for white dwarfs, but whose mass is not great enough to overcome the neutron degeneracy pressure to become black holes.
There are 37 known neutron stars in human space.
A typical neutron star has an M25 limit of between 1000 and 2500 AU, and none have been found to have habitable planets (the vast majority do not have planets at all).
Such stars are composed almost entirely of neutrons, Neutron stars are very hot and are supported against further collapse by quantum degeneracy pressure due to the Pauli exclusion principle.
Some neutron stars also exhibit rotational effects that produce high power electromagnetic emissions. These are known as Pulsars. The nearest Pulsar to Earth is PSR J0108-1431, and is 85 parsecs away in Quadrant 8.