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Astronomy

How Gravitational Wave Observatories Detect Merging Black Holes

Quick fact

LIGO's detectors can measure changes in length as small as 1/10,000th the width of a proton—equivalent to detecting a change in the distance from Earth to the nearest star of just a few millimeters.

Why this is interesting

Imagine detecting ripples in the fabric of space itself, caused by black holes crashing together billions of light-years away. How can we possibly measure something so tiny?