What is a neutron star known for due to its extreme density?

A neutron star is indeed known for being the smallest and densest type of star. Following a supernova explosion, a star that has exhausted its nuclear fuel can collapse under its own gravity, compressing its core to such an extent that protons and electrons combine to form neutrons. This process leads to an incredibly compact object primarily composed of neutrons, resulting in densities exceeding that of an atomic nucleus, often more than a million times denser than the Sun.

Compared to other forms of stars, neutron stars are relatively small in size—typically only about 20 kilometers in diameter—yet they can contain more mass than the Sun. This extreme density is what distinguishes them from other stellar remnants, like white dwarfs, and contributes to their fascinating properties, such as powerful magnetic fields and rapid rotation rates.