Callirrhoe (moon)
|
Spacewatch image from 1999 | |
| Discovery[1] | |
|---|---|
| Discovered by | Spacewatch |
| Discovery site | Kitt Peak National Observatory[2] |
| Discovery date | Oct-Nov 1999 |
| Designations | |
|
S/1999 J 1[1] 1999 UX18[1][3] | |
| Orbital characteristics[4] | |
| 24,099,000 km | |
| Eccentricity | 0.2796 |
| 758.82 d (2.1 yr) | |
| 107.962° | |
| Inclination | 147.080° |
| 283.104° | |
| 23.909° | |
| Satellite of | Jupiter |
| Physical characteristics | |
| Dimensions | ~8.6 km[5] |
| Albedo | 0.04 (assumed) |
| 20.7[5] | |
|
| |
Callirrhoe (/kəˈlɪroʊˌiː/ kə-LIRR-o-ee; Greek: Καλλιρρόη), also known as Jupiter XVII (17), is one of Jupiter's outermost named natural satellites. It is an irregular moon that orbits in a retrograde direction. Callirrhoe was imaged by Spacewatch at Kitt Peak National Observatory from October 6 through November 4, 1999,[2] and originally designated as asteroid (1999 UX18).[3][6] It was discovered to be in orbit around Jupiter by Tim Spahr on July 18, 2000, and then given the designation S/1999 J 1.[1][7] It was the 17th confirmed moon of Jupiter.[2]
Callirrhoe has an apparent magnitude of 20.7,[5] making it even fainter than dwarf planet Eris at magnitude 18.7.[8] Jupiter is about 2.5 billion times brighter than Callirrhoe.[9]
Callirrhoe is about 8.6 kilometers in diameter,[5] and orbits Jupiter at an average distance of 24.1 million kilometers in 758 days, at an inclination of 141° to the ecliptic (140° to Jupiter's equator) with an eccentricity of 0.28. This object was probably captured long ago from a heliocentric orbit and the Sun's gravitational influence makes this orbit highly erratic.[2]
It was named in October 2002 after Callirrhoe, daughter of the river god Achelous, one of Zeus' (Jupiter's) many conquests.[10]
It belongs to the Pasiphae group, irregular retrograde moons orbiting Jupiter at distances ranging between 22.8 and 24.1 million kilometers, and with inclinations ranging between 144.5° and 158.3°.
As a navigation exercise, the New Horizons spacecraft imaged it on January 10, 2007.[11]
References
- 1 2 3 4 Brian G. Marsden (2000-07-20). "IAUC 7460: S/1999 J 1". IAU.
- 1 2 3 4 "New Outer Satellite of Jupiter Discovered". Minor Planet Center. Retrieved 2009-07-23.
- 1 2 "New moon of Jupiter found". SpaceFlight Now (University of Arizona News Release). Retrieved 2009-07-23.
- ↑ Jacobson, R.A. (2013) JUP300 (2013-08-23). "Planetary Satellite Mean Orbital Parameters". JPL/NASA. Retrieved 2015-11-27.
- 1 2 3 4 "Planetary Satellite Physical Parameters". JPL (Solar System Dynamics). 2009-04-03. Retrieved 2009-07-23.
- ↑ MPS 7418 (Minor Planet Circulars Supplement); not available on-line
- ↑ MPEC 2000-Y16: S/1975 J 1 = S/2000 J 1, S/1999 J 1 2000-12-19 (discovery and ephemeris)
- ↑ "AstDys (136199) Eris Ephemerides". Department of Mathematics, University of Pisa, Italy. Retrieved 2009-03-16.
- ↑ (5th root of 100)^(20.7-(-2.8))=2.51 billion
- ↑ IAUC 7998: Satellites of Jupiter 2002 October 22 (naming the moon)
- ↑ http://www.planetary.org/blogs/emily-lakdawalla/2007/jupiter_timeline.html