02 September 2010
Credit: NASA/JPL/Space Science Institute
NASA recently published an image of Telesto, a tiny bizarre moon of Saturn. The image was acquired by the Saturn-orbiting Cassini spacecraft. Unlike the majority of the planetary moons, the surface of icy Telesto is smooth, with few impact craters. This astonishing lack of craters on Telesto is believed to be due to a fine dust-sized icy material, covering the moon’s surface.
The image was captured when the Cassini spacecraft flew by Telesto, on 27 August, 2009. It was taken in visual light with the narrow-angle camera onboard Cassini, at a distance of approximately 36,000 km from Telesto. North on Telesto is up and rotated 3 degrees to the right.
Potato-like Telesto is only 25 km across, while Titan, Saturn’s largest moon, is 5,150 km across. Telesto’s gravity is too weak to render it a round shape. Telesto orbits Saturn every 1.9 day, at an average distance of approximately 295,000 km. For comparison, the Moon (3,476 km across) orbits Earth every 27.3 days, at an average distance of about 384,000 km.
Further Reading
The Cassini Mission Homepage
http://saturn.jpl.nasa.gov/
Flying by a Cosmic Iceberg
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References
Smooth Telesto
http://photojournal.jpl.nasa.gov/catalog/PIA12704
Aymen Mohamed Ibrahem
Senior Astronomy Specialist