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Astronomy

How Gravitational Waves Reveal Neutron Star Interiors

Quick fact

The gravitational-wave signal from a neutron star merger is so sensitive to the stars' internal structure that it can reveal whether the matter inside is 'squishy' or 'stiff', allowing astronomers to infer the kind of particles that exist at the core.

Why this is interesting

When two neutron stars spiral together and collide, they briefly shake the fabric of space itself. Could those ripples carry the secret of what's inside these city-sized stars?