Ice volcanoes on Enceladus, Saturn’s small icy moon
Plumes of cold material, erupting from the southern polar region of a small geologically-active Saturnian moon, known as Enceladus. The image was taken by the Saturn-orbiting Cassini spacecraft, when it flew by Enceladus, on 1 October 2011.
Credit: NASA/JPL-Caltech/Space Science Institute
On 1 October 2011, NASA's Saturn-orbiting Cassini spacecraft flew by Saturn's intriguing moon Enceladus, and imaged its active ice volcanoes, which spew cold jets of water vapor and ice. Cassini approached Enceladus to within only 100 km. The close encounter was planned to allow Cassini's instruments to "taste" the jets.
The plume-like jets were discovered by Cassini in 2005. They represent a rare type of volcanism, known as ice volcanoes, or cryovolcanoes. Ice volcanoes occur on cold bodies, such as Enceladus or Triton, Neptune’s largest moon. They erupt ices and volatiles, instead of incinerating lavas and hot gases.
Enceladus (504 km across) is a small bizarre moon. Its icy surface shows varied terrain, and is very bright, reflecting most of incident sunlight. Enceladus orbits Saturn every 1.37 days, at an average distance of approximately 240,000 km. Like our Moon, Enceladus keeps the same side turned to its planet, since the time it takes to rotate once about its axis is equal to its orbital period. The name Enceladus comes from Greek mythology.
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nterestingly, Cassini will encounter Enceladus anew, on 19 October, when the spacecraft flies about 1,200 km from Enceladus’ surface.
References
NASA
www.nasa.gov/
Wikipedia
Further Reading
Cassini’s Homepage
http://saturn.jpl.nasa.gov