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Astronomy

Exomoon Detection Through Transit Timing Variations

Quick fact

A single moon can cause a planet's transit to arrive up to a few minutes early or late, and the pattern of those deviations repeats with the moon's orbital period.

Why this is interesting

If a planet like Jupiter orbited a distant star, its giant moons would be almost impossible to see. Yet they might still be detectable—just by looking at when the planet passes in front of its star.