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Astronomy

The Evolution of Pulsar Spin-Down Over Cosmic Timescales

Quick fact

A typical pulsar's rotation slows by about one microsecond per year—a tiny but measurable change that confirms it is losing energy. Yet some pulsars occasionally speed up in a dramatic event called a glitch, momentarily reversing the trend.

Why this is interesting

You might think that a spinning star would slow down smoothly, but some pulsars actually speed up in a sudden 'glitch'. How can the steady drumbeat of a pulsar change over millions of years?