23 September 2007
Credit: NASA/JPL/Space Science Institute
NASA recently published an interesting image of Hyperion, Saturn's enigmatic deformed moon. The image was acquired by the Saturn-orbiter Cassini spacecraft.
Hyperion (280 km across) is the largest irregularly-shaped moon in the Solar System. Hyperion has a very low density, about half that of water. Owing to its weak gravity, meteoroids tend to compress Hyperion's surface rather than excavating, it and the resulting debris are mostly flung into space.
Hyperion is also the only planetary moon known to rotate chaotically. Hyperion's rotational axis does not have a fixed orientation in space, and the moon resembles a tumbling rock.
The image was taken in green light with Cassini's narrow-angle camera on 23 July 2007. The view was obtained at a distance of approximately 318,000 km from Hyperion. Image scale is 2 km per pixel.
Further Reading
Cassini-Huygens Mission to Saturn
http://saturn.jpl.nasa.gov/home/index.cfm
Aymen Mohamed Ibrahem
Senior Astronomy Specialist