Enceladus

Saturn II

Enceladus Facts

• Enceladus is the eighth of Saturn's known satellites:
  • distance from Saturn: 238,020 km
  • diameter: 500 km
  • mass: 8.40e19 kg

• Pronounced "en SEL a dus".

• In Greek mythology Enceladus was a Titan who was defeated in battle and buried under Mount Etna by Athena.

• Discovered in 1789 by Herschel.

• Enceladus has the highest albedo (>0.9) of any body in the solar system. Its surface is dominated by fresh, clean ice.

• At least five different types of terrain have been identified on Enceladus. In addition to craters there are smooth plains and extensive linear cracks and ridges. At least some of the surface is relatively young, probably less than 100 million years.

• This means that Enceladus must have been active until very recently (and perhaps is still active today). Perhaps some sort of "water volcanism" is at work.

• Enceladus is much too small to still be heated by the decay of radioactive material in its interior (the heat would have all dissipated long ago).

• Enceladus is locked in a 1:2 resonance with Dione (similar to the situation between Io and Europa). This may provide a heating mechanism but it is probably insufficient to melt water ice. Enceladus may therefore be composed of some low-melting point material rather than pure water.

• Enceladus may be the source of the material in Saturn's tenuous E ring. And since the material cannot persist in the ring for more than a few thousand years, it may be due to very recent activity on Enceladus. Another possibility, though, is that the rings are maintained by high-velocity collisions between dust particles and the various moons.

Pictures

1. (above) Voyager image of Saturn moon Enceladus 168k gif; 258k gif; 32k jpg
2. Enceladus Global Mosaic 71k gif; 188k jpg
3. Enceladus, moon of Saturn 60k gif
4. Enceladus, moon of Saturn 28k gif
5. Enceladus, moon of Saturn, closer image 72k gif
6. Enceladus, moon of Saturn, close image 69k gif
7. Enceladus, moon of Saturn, closest full view image 183k gif
8. Enceladus, moon of Saturn, close and chopped off 204k gif

9. Enceladus low res color 42k jpg

Movies

1. Flight over Enceladus 3300k AVI

More about Enceladus

• from LANL

Open Issues

• What is the resurfacing mechanism? where does the energy come from?
• Is there a liquid layer beneath the surface?