# Occultation

When one object passes in front of another and hides it — the Moon covering a star or planet, say.

As the Moon moves eastward against the stars, it covers (occults) stars and sometimes planets. A star blinks out instantly at the Moon's edge — proof that the Moon has no atmosphere. Jupiter occults its own moons, too, as they pass behind it.

**Examples:** [moon](https://astropilot.space/object/moon.md), [jupiter](https://astropilot.space/object/jupiter.md), [io](https://astropilot.space/object/io.md)

**Related:** [Conjunction](https://astropilot.space/glossary/conjunction.md), [Transit](https://astropilot.space/glossary/transit.md), [Eclipse](https://astropilot.space/glossary/eclipse.md), [Galilean moons](https://astropilot.space/glossary/galilean-moons.md)

From the AstroPilot astronomy glossary: https://astropilot.space/glossary/occultation