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Astronomy

Using Pulsar Timing Arrays to Detect Gravitational Waves

Quick fact

Pulsar timing arrays are sensitive to gravitational waves with wavelengths of light-years, which is why they require monitoring for over a decade. In 2023, several collaborations announced the first evidence of a background hum of such waves, likely from supermassive black hole mergers.

Why this is interesting

You've probably heard of using lasers to detect ripples in spacetime, but did you know that a network of dead stars can do the same thing? How can we 'listen' to the universe's deepest hum using cosmic clocks?