Pandora (moon)
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- There is also an asteroid called 55 Pandora.
 Pandora, as imaged by Cassini |
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| Discovery | |||||||
|---|---|---|---|---|---|---|---|
| Discovered by | Collins, Voyager 1 | ||||||
| Discovered in | October, 1980 | ||||||
| Orbital characteristics [1] | |||||||
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| Semimajor axis | 141,720 ± 10 km | ||||||
| Eccentricity | 0.0042 | ||||||
| Revolution period | 0.628504213 d | ||||||
| Inclination to Saturn's equator |
0.050 ± 0.004° | ||||||
| Is a satellite of | Saturn | ||||||
| Physical characteristics | |||||||
| Diameter | 81 km (103×80×64 km) [2] | ||||||
| Surface area | ~21,000 km² | ||||||
| Volume | ~270,000 km³ | ||||||
| Mass | 1.356 ± 0.022 ×1017 kg [1] | ||||||
| Mean density | 0.49 ± 0.08 g/cm³ | ||||||
| Surface gravity | 0.0034 m/s2 | ||||||
| Escape velocity | ~0.019 km/s | ||||||
| Rotation period | synchronous | ||||||
| Axial tilt | zero | ||||||
| Albedo | 0.6 | ||||||
| Surface temp. |
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| Atmospheric pressure | none | ||||||
Pandora (pan-dor'-a, IPA: [pænˈdɔrə], Greek Πανδώρα) is an inner satellite of Saturn. It was discovered in 1980 from photos taken by the Voyager 1 probe, and was designated 1980 S 26.[3] In 1985 it was officially named after Pandora from Greek mythology. It is also designated as Saturn XVII.[4]
Pandora is the outer shepherd satellite of the F Ring. It is more heavily cratered than nearby Prometheus, and has at least two large craters 30 km in diameter.[citation needed]
From its very low density and relatively high albedo, it seems likely that Pandora is a very porous icy body. There is a lot of uncertainty in these values, however, so this remains to be confirmed.[citation needed]
The orbit of Pandora appears to be chaotic, as a consequence of a mean motion resonance with Prometheus. The most appreciable changes in their orbits occur approximately every 6.2 years [1], when the periapsis of Pandora lines up with the apoapsis of Prometheus and the moons approach to within about 1400 km. Pandora also has a 3:2 mean-motion resonance with Mimas [1].
[edit] References
- ^ a b c d 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.
- ^ 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.
- ^ Smith, B. A. (October 31, 1980). IAU Circular No. 3532. Retrieved on 2006-08-07.
- ^ Planet and Satellite Names and Discoverers. Gazetteer of Planetary Nomenclature. USGS Astrogeology (July 21, 2006). Retrieved on 2006-08-07.
[edit] External links
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| 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 |
