Quark

Artist's impression of the different layers inside a massive neutron star, with the red circle representing a large quark-matter core. Credit Jyrki Hokkanen, CSC

More evidence for quarks at the centers of massive neutron stars

A new theoretical analysis puts the probability that massive neutron stars harbor non-configurational quark nuclei between 80 and 90 percent. The result was achieved through massive computer runs using Bayesian statistical inference.
Imaging the quarks inside the pentaquark particle. Figure CERN

What is the material made of?