Callirrhoe (moon)
Callirrhoe (/kəˈlɪroʊ.iː/;[6] Greek: Καλλιρρόη), also known as Jupiter XVII, is one of Jupiter's outer 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][7] 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][8] It was the 17th confirmed moon of Jupiter.[2]
![]() Spacewatch discovery image from 1999 | |
Discovery[1] | |
---|---|
Discovered by | Spacewatch |
Discovery site | Kitt Peak National Observatory[2] |
Discovery date | October 1999 |
Designations | |
Designation | Jupiter XVII |
Orbital characteristics [4] | |
24102000 km | |
Eccentricity | 0.283 |
−758.82 d (2.1 yr) | |
321.7° | |
Inclination | 147.080° |
283.104° | |
49.3° | |
Satellite of | Jupiter |
Group | Pasiphae group |
Physical characteristics | |
Mean diameter | 9.6±1.3 km[5] |
Albedo | 0.052±0.016[5] |
20.8 | |
Name
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It was named in October 2002 after Callirrhoe, daughter of the river god Achelous, one of Zeus' (Jupiter's) many conquests.[9]
Characteristics
Callirrhoe has an apparent magnitude of 20.7,[10] making it even fainter than dwarf planet Eris at magnitude 18.7.[11] Jupiter is about 2.5 billion times brighter than Callirrhoe.[12]
Callirrhoe is about 9.6 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 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°.
Exploration
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As a navigation exercise, the New Horizons spacecraft imaged Callirrhoe on January 10, 2007.[13]
References
- Brian G. Marsden (July 20, 2000). "IAUC 7460: S/1999 J 1". IAU. Archived from the original on April 26, 2006. Retrieved November 22, 2005.
- "New Outer Satellite of Jupiter Discovered". Minor Planet Center. Retrieved July 23, 2009.
- "New moon of Jupiter found". SpaceFlight Now (University of Arizona News Release). Retrieved July 23, 2009.
- S.S. Sheppard (2019), Moons of Jupiter, Carnegie Science, on line
- Grav, T.; Bauer, J. M.; Mainzer, A. K.; Masiero, J. R.; Nugent, C. R.; Cutri, R. M.; et al. (August 2015). "NEOWISE: Observations of the Irregular Satellites of Jupiter and Saturn". The Astrophysical Journal. 809 (1): 9. Bibcode:2015ApJ...809....3G. doi:10.1088/0004-637X/809/1/3. 3.
- Noah Webster (1884) A Practical Dictionary of the English Language
- 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)
- IAUC 7998: Satellites of Jupiter 2002 October 22 (naming the moon)
- "Planetary Satellite Physical Parameters". JPL (Solar System Dynamics). April 3, 2009. Retrieved July 23, 2009.
- "AstDys (136199) Eris Ephemerides". Department of Mathematics, University of Pisa, Italy. Retrieved March 16, 2009.
- (5th root of 100)^(20.7-(-2.8))=2.51 billion
- "New Horizons Jupiter Encounter Timeline". www.planetary.org.