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Prometheus, Saturn's moon

 Automatic translation  Automatic translation Updated June 01, 2013

Prometheus discovered in October 1980, is an irregular natural satellite of Saturn, which has a size measured in 2006 of 119 x 87 x 61 km.
The moon has many valleys and cliffs and craters more than twenty kilometers in diameter.
Prometheus seems less cratered than the neighboring moons, Pandora, Janus and Epimetheus.
Its low density and high albedo suggests that Prometheus is a star ice very porous.

Image: Prometheus in the foreground above the F ring and in the F ring, we see Pandora.
Credit: NASA Cassini imaging team.

 Prométhée satellite de Saturne 
Prometheus Moon of Saturn
Dimensions 119 x 87 x 61 km
Mass 1.6×1017 kg
Mean density  480 kg/m3
Average albedo 0,6
Semi-major axis 139 400 km
Eccentricity  0.0023
Orbital period  0.612990038 d
Discovered October 1980
Discovered by Stewart A. Collins (Voyager 1)
Rotation period synchronous

Prometheus creates waves in the rings


Prometheus continually creating strange currents in the F ring of Saturn.
This small moon revolves around Saturn within the thin F ring and near the inner edge of the ring every 15 hours.
Thus, the low gravity field of Prometheus then attracts fine particles of ice dust around, causing the dark waves, lack of material. Prometheus creates a new stream on each pass, so that sometimes several of them are visible simultaneously.
The gravity field of the tiny moon creates waves, channels and nodes in the F ring and the dark waves visible in this image.

NB: In Greek mythology, Prometheus was the one who stole fire from the gods.


Image: In this image, Prometheus is visible in the upper left, the moon of Saturn is orbiting near the inner edge of Saturn's F ring.
This view shows the many narrow fringes of the F ring and a low strip of material connecting Prometheus to the ring.
Picture taken in January 2009 by the Cassini spacecraft.
Credit: Cassini Imaging Team ISS, JPL, ESA, NASA.

 prométhée et les anneaux de saturne

Prometheus, the shepherd satellite


Prometheus (Prometheus S XVI), the small moon of Saturn has been observed in detail by the Cassini-Huygens space probe, shows it in its 119 km long. Orbiting Saturn since 2004, the Cassini spacecraft has completed end January 2010, his closest overview of Prometheus. In fact this image was taken by Cassini, from a distance of 36 000 km. The surface of Prometheus which covers 119 x 87 x 61 km, shows an interesting and complex system of ridges, projections and craters. These courses added to its oval shape and its high reflectivity, are now studied in the hope of better understanding the relationship that exists between Prometheus and Saturn's rings.
Prometheus is indeed one of the few known shepherd moons of Saturn.


Like that of its companion moon, Pandora, Prometheus bordering many small pieces of ice in Saturn's F ring. In this picture, part of Prometheus (right) is illuminated by the Sun while the other remains still visible due to reflection of sunlight on Saturn.

Image: Credit: Cassini Imaging team ISS, JPL, ESA, NASA.

NB: shepherd satellite is a body of a modest size orbiting near the edge of a ring. The gravity generated by the satellite and it confines the ring defines an exact edge. Indeed, the materials are either sent them away in the ring, or ejected from it, or integrate with the moon.
 prométhée ou prometheus, lune de Saturne

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