When a very massive star collapses and a supernova explosion occurs, a remnant can persist, a kind of stellar corpse known as a neutron star. In it, matter is at such high pressures that it does not appear in the form of atoms, but in a kind of paste of neutrons and other subatomic particles.
It is the strongest substance known: it has a density one trillion times that of water and to break it we would have to exert a force one billion times greater than that necessary to break steel. That is, at least, what a team of astrophysicists assures in an article published in the journal Physical Review Letters . In it, scientists indicate that one kilometer below the surface of a neutron star, nuclear matter is extraordinarily compressed ; so much so that it forms peculiar structures that these researchers have compared with different types of Italian pasta.
Thus, some are rounded, like gnocchi; others stretch like spaghetti; and there are thin and flat, like lasagna.
How is a neutron star formed?
When a massive star ends its life as a supernova, it shoots its outer layers back into interstellar space. At this moment, the spectacular explosion of death is initiated by the collapse of what has become an incredibly dense stellar core. However, this core is not necessarily destroyed. Instead, it can transform into an exotic object with the density of an atomic nucleus but with a mass greater than that of the Sun: a neutron star.
A neutron star is difficult to detect directly because it is small (about 10 miles across) and therefore faint, but newly formed in this violent crucible it is intensely hot, glowing in X-rays. X-ray images of the ROSAT observatory in orbit can offer a prime view of an X-ray glow of such newly formed neutron stars. The Puppis A supernova is one of the brightest sources in the sky of X-rays, with clouds of gas in shock that are still expanding and radiating X-rays. A weak and point X-ray source is probably a young neutron star, ejected the asymmetric explosion and moving away from the original supernova site at approximately 956 kilometers per second.
