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Astronomy

The Search for Exomoon Populations Using Transit Timing Variations

Quick fact

Transit timing variations are so sensitive that they can detect a moon only slightly larger than Ganymede (around 1.5 Earth masses) tugging on its host planet, even though the moon itself is invisible to our telescopes.

Why this is interesting

Have you ever wondered if distant planets have moons like our very own? Astronomers now think they might be close to finding out—not by seeing them, but by watching the planet's punctuality.