LIGO Gravitational Wave Detection

LIGO achieved the most precise confirmation of general relativity in history by directly detecting ripples in spacetime from two merging black holes 1.3 billion light-years away. The experiment measured a strain of just 10^-21, equivalent to changing the distance to the nearest star by a hair's width—a sensitivity 100 times greater than the original detectors. This breakthrough outperforms #2 Eddington's eclipse expedition as a direct test of spacetime dynamics, providing real-time data from cosmic collisions rather than a single solar observation.