Atlas (moon)
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 Atlas, as imaged by Cassini on June 8, 2005 | |||||||
| Discovery | |||||||
|---|---|---|---|---|---|---|---|
| Discovered by | Terrile, Voyager 1 | ||||||
| Discovered in | October, 1980 | ||||||
| Orbital characteristics <ref name="Spitale06">J.N. Spitale et al (2006). "The orbits of Saturn's small satellites derived from combined historic and Cassini imaging observations". The Astronomical Journal 132: 692.</ref> | |||||||
| Mean radius | 137,670 ± 10 km | ||||||
| Eccentricity | 0.0012 | ||||||
| Orbital period | 0.6016947883 d | ||||||
| Inclination | 0.003 ± 0.004° | ||||||
| Satellite of | Saturn | ||||||
| Physical characteristics | |||||||
| Mean diameter | 31 km (46 × 38 × 19 km) <ref name="Porco06">C.C. Porco et al. (2006). "Physical characteristics and possible accretionary origins for Saturn's small satellites". Bulletin of the American Astronomical Society 37: 768.</ref> | ||||||
| Surface area | ~3,700 km² | ||||||
| Volume | ~15,000 km³ | ||||||
| Mass | 6.6 ± 0.6 ×1015 kg <ref name="Spitale06"/> | ||||||
| Mean density | 0.44 ± 0.11 g/cm³ | ||||||
| Surface gravity | ~0.00083 m/s2 | ||||||
| Escape velocity | ~0.0062 km/s | ||||||
| Rotation period | synchronous | ||||||
| Axial tilt | zero | ||||||
| Albedo | 0.4 | ||||||
| Surface temperature |
| ||||||
| Atmospheric pressure | none | ||||||
Atlas (at'-ləs, IPA: [/ˈætləs/], Greek Άτλας) is an inner satellite of Saturn.
Atlas was discovered by Richard Terrile in 1980 (some time before November 12) from Voyager photos and was designated S/1980 S 28. In 1983 it was officially named after Atlas of Greek mythology, because it "holds the rings on its shoulders" like the Titan Atlas held the sky up above the Earth. It is also designated as Saturn XV.
Atlas seems to be a shepherd satellite of the A ring. Furthermore, in 2004 a faint, thin ring, temporarily designated R/2004 S 1, was discovered within Atlas's orbit.
High-resolution images taken in June 2005 by Cassini reveal a saucer-shaped moon with a large equatorial ridge.
Atlas is significantly perturbed by Prometheus and to a lesser degree by Pandora, leading to excursions in longitude of up to 600 km (~0.25°) away from the precessing keplerian orbit with a rough period of about 3 years. Since the orbits of Prometheus and Pandora are chaotic, it is suspected that Atlas's may be as well <ref name="Spitale06"/>.
[edit] References
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[edit] External links
| edit Saturn's natural satellites |
|---|
| Pan · Daphnis · Atlas · Prometheus · S/2004 S 6 · S/2004 S 4 · S/2004 S 3 · Pandora · Epimetheus and Janus Mimas · Methone · Pallene · Enceladus · Telesto, Tethys, and Calypso · Helene, Dione, and Polydeuces · Rhea · Titan · Hyperion · Iapetus Kiviuq · Ijiraq · Phoebe · Paaliaq · Skathi · Albiorix · S/2004 S 11 · Erriapo · S/2006 S 8 · Siarnaq · S/2004 S 13 · S/2006 S 4 · Tarvos S/2004 S 19 · Mundilfari · S/2006 S 6 · S/2006 S 1 · S/2004 S 17 · Narvi · S/2004 S 15 · S/2004 S 10 · Suttungr · S/2004 S 12 · S/2004 S 18 S/2004 S 9 · S/2004 S 14 · S/2004 S 7 · Thrymr · S/2006 S 3 · S/2006 S 7 · S/2006 S 2 · S/2004 S 16 · S/2006 S 2 · Ymir · S/2006 S 5 · S/2004 S 8 |
| See also: Pronunciation key | Rings of Saturn | Cassini-Huygens | Themis |
bg:Атлас (спътник) ca:Atles (satèl·lit) cs:Atlas (měsíc) da:Atlas (måne) de:Atlas (Mond) es:Atlas (luna) fr:Atlas (lune) hr:Atlas (mjesec) it:Atlante (astronomia) nl:Atlas (maan) ja:アトラス (衛星) no:Atlas (måne) nn:Saturnmånen Atlas pl:Atlas (księżyc) pt:Atlas (satélite) ru:Атлас (спутник) sk:Atlas (mesiac) sv:Atlas (måne) uk:Атлас (супутник) zh:土卫十五
