Crazy Stars

Stars like our Sun are considered “ordinary” and quite common. They produce energy through hydrogen fusion. A weirder type of star is a white dwarf. These are stars that at one point produced energy through hydrogen fusion, but have run out of hydrogen, and do not have the mass to carry out fusion energy reactions with heavier elements. Instead, these white stars sit idle, cooling down for billions of years. A white dwarf star has about the mass of our sun, with about the diameter of earth. The atoms within a white star are packed so tightly together that they exert an outward degeneracy pressure, as the particles are packed as tightly together as the laws of quantum mechanics allow. 

Another type of weird star is the neutron star. Created by the collapse of a star’s core during a supernova, these stars are only 10 km across, but with a mass greater than the sun. They are made almost entirely of neutrons, as protons and electrons within it are so closely packed that they combine into neutrally charged neutrons. In fact, if a 10km wide neutron star appeared in Nashville, it would condense the entire earth into a size no thicker than your thumb. Really crazy!

White Dwarf Illustration – Courtesy of NASA