Neutron stars
A neutron star is the extremely dense core left behind after a massive star explodes as a supernova. These cosmic objects are among the densest things in the universe, second only to black holes. Despite having roughly 1.4 solar masses—about as much as our Sun—a neutron star squeezes into a sphere just 10 kilometers across. This incredible density means that a matchbox-sized chunk of neutron star material would weigh 3 billion tonnes. Neutron stars matter because they serve as natural laboratories for understanding extreme physics and are crucial for studying gravitational waves, the ripples in spacetime. When two neutron stars collide, they produce gravitational waves that help astronomers unlock mysteries about the fundamental nature of matter and the universe itself.
Sources
- en.wikipedia.org: “A neutron star is the gravitationally collapsed core of a massive supergiant star. It results from the supernova explosion of a massive star—combined with gravitational collapse—that compresses the core past white dwarf star density to that of atomic nuclei.”
- en.wikipedia.org: “Surpassed only by black holes, neutron stars are the second-smallest and second-densest known class of stellar objects. Neutron stars have a radius on the order of 10 kilometers (6 miles) and a mass of about 1.4 solar masses (M☉).”
- en.wikipedia.org: “Neutron star material is remarkably dense: a normal-sized matchbox containing neutron-star material would have a weight of approximately 3 billion tonnes, the same weight as a 0.5-cubic-kilometer chunk of the Earth (a cube with edges of about 800 meters) from Earth's surface.”
- en.wikipedia.org: “The study of neutron star systems is central to gravitational wave astronomy. The merger of binary neutron stars produces gravitational waves and is associated with kilonovae and short gamma-ray bursts.”