the neutron star

This image presents a composite of X-rays from Chandra (red, green, and blue) and optical data from Hubble (gold) of Cassiopeia A, the remains of a massive star that exploded in a supernova. Inset: A cutout of the interior of the neutron star, where densities increase from the crust (orange) to the core (red) and finally to the region where the "superfluid" exists (inner red ball). CREDIT: X-ray: NASA/CXC/xx; Optical: NASA/STScI; Illustration: NASA/CXC/M.Weiss View full size image

The ultradense core of an exploded star contains a bizarre form of superconducting matter called a superfluid