Calypso (moon)
 | |
| Discovery | |
|---|---|
| Discovered by | Pascu, Seidelmann, Baum and Currie |
| Discovery date | March 13, 1980 |
| Designations | |
| Adjectives | Calypsonian |
| Orbital characteristics | |
| 294,619 km | |
| Eccentricity | 0.000 |
| 1.887802 d[1] | |
| Inclination | 1.56° (to Saturn's equator) |
| Satellite of | Saturn |
| Physical characteristics | |
| Dimensions | 30 × 23 × 14 km[2] |
Mean radius | 10.7 ± 1.0 km[2] |
| synchronous | |
| zero | |
| Albedo | 1.34 ± 0.10 (geometric)[3] |
Calypso (Template:PronEng kə-LIP-soh, or as in Greek Καλυψώ) is a moon of Saturn. It was discovered by Pascu, Seidelmann, Baum and Currie in 1980 from ground-based observations, and was provisionally designated S/1980 S 25.[4] Several other apparitions of it were recorded in the following months: S/1980 S 29, S/1980 S 30,[5] S/1980 S 32,[6] and S/1981 S 2.[7]
In 1983 it was officially named after Calypso of Greek mythology[8]. It is also designated as Saturn XIV or Tethys C.
Calypso is co-orbital with the moon Tethys, and resides in Tethys' trailing Lagrangian point (L5) 60 degrees behind Tethys. This relationship was first identified by Seidelmann et al. in 1981.[9] The moon Telesto also resides in the other (leading) lagrangian point of Tethys, 60 degrees in the other direction from Tethys.
Like many other small Saturnian moons and small asteroids, Calypso is irregularly shaped, has overlapping large craters, and appears to also have loose surface material capable of smoothing the craters' appearance. Its surface is one of the most reflective (at visual wavelengths) in the solar system, with a visual geometric albedo of 1.34.[3] This very high albedo is the result of the sandblasting of particles from Saturn's E-ring, a faint ring composed of small, water-ice particle generated by Enceladus' south polar geysers.
Not to be confused with asteroid 53 Kalypso.
References
- ^ NASA Celestia
- ^ a b Porco, C. C.; et al. (2006). "Physical Characteristics and Possible Accretionary Origins for Saturn's Small Satellites" (PDF). Bulletin of the American Astronomical Society. 37: 768.
{{cite journal}}: Explicit use of et al. in:|author=(help) - ^ a b Verbiscer, A.; French, R.; Showalter, M.; and Helfenstein, P.; Enceladus: Cosmic Graffiti Artist Caught in the Act, Science, Vol. 315, No. 5813 (February 9, 2007), p. 815 (supporting online material, table S1)
- ^ IAUC 3496: Satellites of Saturn July 31, 1980 (discovery)
- ^ IAUC 3549: Satellites of Saturn December 11, 1980
- ^ IAUC 3605: Satellites of Saturn May 18, 1981
- ^ IAUC 3593: Satellites of Saturn April 16, 1981
- ^ Transactions of the International Astronomical Union, Vol. XVIIIA, 1982 (confirms Janus, names Epimetheus, Telesto, Calypso) (mentioned in IAUC 3872: Satellites of Jupiter and Saturn, September 30, 1983)
- ^ Seidelmann, P. K.; Harrington, R. S.; Pascu, D.; Baum, W. A.; Currie, D. G.; Westphal, J. A.; and Danielson, G. E.; Saturn Satellite Observations and Orbits from the 1980 Ring Plane Crossing, Icarus, Vol. 47 (August 1981), pp. 282–287