E-Mail IMAGE: The physics of massive nuclei can be studied by measuring the 'note' at which tidal resonance between merging neutron stars causes the solid crust of the neutron stars to shatter view more Credit: University of Bath Space scientists at the University of Bath in the UK have found a new way to probe the internal structure of neutron stars, giving nuclear physicists a novel tool for studying the structures that make up matter at an atomic level. Neutron stars are dead stars that have been compressed by gravity to the size of small cities. They contain the most extreme matter in the universe, meaning they are the densest objects in existence (for comparison, if Earth were compressed to the density of a neutron star, it would measure just a few hundred meters in diameter, and all humans would fit in a teaspoon). This makes neutron stars unique natural laboratories for nuclear physicists, whose understanding of the force that binds sub-atomic particles is limited to their work on Earth-bound atomic nuclei. Studying how this force behaves under more extreme conditions offers a way to deepen their knowledge.