30 August 2010
Credit: NASA/JPL/Space Science Institute
NASA recently published a breathtaking view of Saturn, the wonderful ringed planet, and its small geologically active moon Enceladus. The image was acquired by the Saturn-bound Cassini spacecraft. Cassini was looking on the night side of giant Saturn (approximately 120,000 km across). The planet was just illuminated by sunlight scattered in its upper atmosphere.
Intriguingly, Enceladus (504 km across) has an amazing type of volcanic activity, termed cryovolcanism, in its south polar region. Cryovolcanoes erupt very cold icy material. In the image, Enceladus, visible beyond Saturn, as a small orb, has a faint plume of icy material, erupting from fissures in its south polar region.
Please visit the following link, for more information on Enceladus’ activity.
http://photojournal.jpl.nasa.gov/catalog/PIA11688
The Cassini spacecraft was about 5 degrees below the plane of Saturn’s magnificent rings, at a distance of approximately 617,000 km from Enceladus. Through image processing, Enceladus’ brightness has been enhanced by a factor of two. The image was taken in visual light, with Cassini’s wide-angle camera, on 25 December 2009.
Cassini was launched toward Saturn in October 1997. It entered orbit around Saturn on 1 July 2004. In its exciting exploration of the Saturn system, Cassini has orbited Saturn more than 125 times, and acquired more than 210,000 images of the planet and its bizarre moons. It is expected that Cassini’s mission will continue till 2017.
Further Reading
Cassini Mission Homepage
http://saturn.jpl.nasa.gov/
References
Activity Past Dark Side
http://photojournal.jpl.nasa.gov/catalog/PIA12705
Aymen Mohamed Ibrahem
Senior Astronomy Specialist