Keeler gap

astronomy

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June 30, 2026

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The Keeler gap is a gap within Saturn's A ring, the outermost of the major rings visible from Earth. This gap is located near the outer edge of the A ring, at approximately 2.26 Saturn radii from the planet's center.1

Planetary rings, like those of Saturn, are disklike aggregations of particles orbiting a planet's equator. These rings are found around the gas giants: Jupiter, Saturn, Uranus, and Neptune. Saturn's rings, composed of rock, ice, and dust, are the most extensively studied. While Saturn's rings are vast in diameter, they are extremely thin. The Keeler gap, along with other structures in Saturn's rings, is a subject of ongoing research, with theories suggesting that moons or gravitational resonances may play a role in their formation and maintenance. Astronomer James Keeler confirmed that Saturn's rings are not solid but are made up of countless tiny particles.213

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Saturn
The ring system
…the A ring; and the Keeler gap (2.26 Saturn radii), almost at the outer edge of the A ring. Of these gaps, only Encke was known prior to spacecraft exploration of Saturn.
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…the A ring; and the Keeler gap (2.26 Saturn radii), almost at the outer edge of the A ring. Of these gaps, only Encke was known prior to spacecraft exploration of Saturn.
Read More