There is also an asteroid called 55 Pandora.
Pandora, as imaged by Cassini | |
Discovery | |
---|---|
Discovered by | Collins, Voyager 1 |
Discovery date | October, 1980 |
Epoch December 31, 2003 (JD 2453005.5 | |
Semi-major axis | 141,720 ± 10 km |
Eccentricity | 0.0042 |
Orbital period | 0.628504213 d |
Inclination | 0.050 ± 0.004° to Saturn's equator |
Satellite of | Saturn |
Physical characteristics | |
Dimensions | 103×80×64 km[2] |
Mean radius | 40.3 ± 2.2 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 |
Equatorial surface gravity | 0.0034 m/s2 |
Escape velocity | ~0.019 km/s |
Rotation period | synchronous |
Axial tilt | zero |
Albedo | 0.6 |
Temperature | ~78 K |
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Pandora (pronounced /pænˈdɔərə/ pan-DOHR-ə, or as in Greek Πανδώρα) is an inner satellite of Saturn. It was discovered in 1980 from photos taken by the Voyager 1 probe, and was provisionally designated S/1980 S 26.[3] In late 1985 it was officially named after Pandora from Greek mythology.[4] It is also designated as Saturn XVII.[5]
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.[6]
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 1,400 km. Pandora also has a 3:2 mean-motion resonance with Mimas.[1]
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.
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