#astrophysics

A neutron star packs more mass than the Sun into a sphere 20 km across. How they form, why pulsars are the most precise clocks in the universe, what magnetars do to spacetime, and what GW170817 told us about dense matter.

LIGO detects displacements smaller than 1/1000th of a proton's diameter. How laser interferometry turns spacetime distortions into data, what the GWTC catalogue has found, and why LISA will open a new gravitational window in the 2030s.