Enceladus

Enceladus shoots giant fountains of ice into space from its south pole!

What it is

Small icy moon with geysers erupting from a hidden subsurface ocean at its south pole.

Moon: Orbits a planet rather than the star. Every kind of thing there is →

How to find Enceladus

Its position moves, so there is no fixed place on a map to point at. The Planetarium works out where it is for your own place and date.

Show me Enceladus in tonight's sky

What you will really see

Through a small telescope, on a good night

A tiny point right beside its bright planet — steady the telescope and wait.

Honest, not glamorous — why the pictures here are drawn.

🔭 See it drawn as it looks through a telescope

Worth knowing about Enceladus

Enceladus is small enough that a determined walker could cross its 500 km of ice in a couple of weeks. In weight, far too light to meaningfully compare to Earth -- about 1/55,000th. Its day: tidally locked; same as its orbital period, 1.37 days.

Its surface: Icy geysers erupt from its south pole, spraying water from a hidden ocean into space.; How we know: Cassini flew straight through the spraying plumes and tasted them with its instruments, detecting salty water and organic molecules directly -- plus careful tracking of Cassini's path revealed a gravity signature matching a sloshing liquid layer under the ice. Rung 3 — the shape of the solar system
How it moves: Just over one day.
The machines we sent: Cassini flew right through the geyser plumes to sample them directly.

The numbers

Across	504 km
Distance from the planet it orbits	237 948 km
Once round its orbit	32.9 hours
One spin	32.9 hours
Made of, among other things	water

How anyone knows this

Nobody flew a tape measure out there. Every number on this page was worked out from the ground:

What it belongs to

☀️ Everything the Sun holds, in one place

Then go outside

Clear tonight? The Planetarium will show you what is worth a look. Then just go out.

🌙 Plan an evening outside 🌌 Everything else in the sky