Pure Neutronium
Michael James Scharen

October 4, 2021

A question came across in Quora on what one might get by mining a neutron star. This was the response I came up with, but others may differ…

Fig.1 - The Doomsday Machine with a hull of pure neutronium. Phasers from the U.S.S. Enterprise could not cut through it.

Assuming one could get close enough without their body or spacecraft being ripped apart by the intense gravity or the incredible temperatures of the surrounding plasma accretion disk, the the product would be pure neutrons. A neutron star is like one giant atomic nucleus made of 99.9999999% neutrons with a few protons maybe at the surface. There is no more dense material than this. Then one would have to pry it apart fighting the strong nuclear force holding it all together. There is an old Star Trek where they encounter a Doomsday Machine (one of my favorite episodes!). One may remember it looked like a big hollow log. Anyway, Spock determined that the hull was made of pure neutronium, which I take to be the same stuff. The material was so dense and strong that their phasers could not blast through it. I suspect that this was basically a solid skin of neutrons which would make sense. Keep in mind that in any material, even the heaviest such as gold or lead, what we see is largely empty space. The electrons are located far away from the nucleus despite the ridiculous logo showing them orbiting like planets. In the original experiment which found the nucleus of the atom, a very thin gold foil was used as a target for very fast alpha particles from a radioactive source. Most of those passed right through or were only slightly deflected from a straight line to a phosphor target. Only a few actually hit a nucleus an bounced backward. With pure neutronium, their would be no vast intervening space between the solid nuclei. The entire sheet would be one solid nucleus. We all know how heavy gold and lead are and their nuclei take up less than 1/1000 of the mass. A thin sheet of neutronium would likely weigh several tons.