Back Kallisto (maan) Afrikaans Kallisto (Mond) ALS Calisto (satelite) AN كاليستو (قمر) Arabic كاليسطو ARY Kallisto (peyk) Azerbaijani کالیستو (قمر) AZB Каллисто (юлдаш) Bashkir Каліста (спадарожнік) Byelorussian Калисто (спътник) Bulgarian
&sq=&lang=&file=File:Callisto_-_July_8_1979_(38926064465).jpg) Callisto imaged in approximately true color by the Voyager 2 spacecraft, July 1979 | |||||||||
| Discovery | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Discovered by | Galileo Galilei Simon Marius | ||||||||
| Discovery date | 7 January 1610[1] | ||||||||
| Designations | |||||||||
| Pronunciation | /kəˈlɪstoʊ/ (kə-LIST-oh)[2] | ||||||||
Named after | Καλλιστώ Kallistō | ||||||||
| Jupiter IV | |||||||||
| Adjectives | Callistoan /ˌkælɪˈstoʊ.ən/ (KAL-iss-TOH-ən) etc. (see text) | ||||||||
| Orbital characteristics | |||||||||
| Periapsis | 1,869,000 km[a] | ||||||||
| Apoapsis | 1,897,000 km[b] | ||||||||
| 1,882,700 km[3] | |||||||||
| Eccentricity | 0.0074[3] | ||||||||
| 16.6890184 d[3] | |||||||||
Average orbital speed | 8.204 km/s | ||||||||
| Inclination | 2.017° (to the ecliptic) 0.192° (to local Laplace planes)[3] | ||||||||
| Satellite of | Jupiter | ||||||||
| Group | Galilean moon | ||||||||
| Physical characteristics | |||||||||
| 2,410.3±1.5 km (0.378 Earths)[4] | |||||||||
| 7.305×107 km2 (0.143 Earths)[c] | |||||||||
| Volume | 5.866×1010 km3 (0.0541 Earths)[d] | ||||||||
| Mass | (1.075938±0.000137)×1023 kg (0.018 Earths)[4] | ||||||||
Mean density | 1.8344±0.0034 g/cm3 (0.333 Earths)[4] | ||||||||
| 1.235 m/s2 (0.126 g)[e] | |||||||||
| 0.3549±0.0042[5] | |||||||||
| 2.441 km/s[f] | |||||||||
| synchronous[4] | |||||||||
| <1°[6] (to Jupiter's equator) | |||||||||
North pole right ascension | 268.72°[6] | ||||||||
North pole declination | 64.83°[6] | ||||||||
| Albedo | 0.22 (geometric)[7] | ||||||||
| |||||||||
| 5.65 (opposition)[8] | |||||||||
| Atmosphere | |||||||||
Surface pressure | 0.75 μPa (7.40×10−12 atm)[9] | ||||||||
| Composition by volume | ≈ 4×108 molecules/cm3 carbon dioxide;[9] up to 2×1010 molecules/cm3 molecular oxygen (O2)[10] | ||||||||
Callisto (/kəˈlɪstoʊ/ kə-LIST-oh), or Jupiter IV, is the second-largest moon of Jupiter, after Ganymede. In the Solar System it is the third-largest moon after Ganymede and Saturn's largest moon Titan, and nearly as large as the smallest planet Mercury. Callisto is, with a diameter of 4,821 km, roughly a third larger than Earth's Moon and orbits Jupiter on average at a distance of 1,883,000 km, which is about five times further out than the Moon orbiting Earth. It is the outermost of the four large Galilean moons of Jupiter,[3] which were discovered in 1610 with one of the first telescopes, and is today visible from Earth with common binoculars.
The surface of Callisto is the oldest and most heavily cratered in the Solar System.[11] Its surface is completely covered with impact craters.[12] It does not show any signatures of subsurface processes such as plate tectonics or volcanism, with no signs that geological activity in general has ever occurred, and is thought to have evolved predominantly under the influence of impacts.[13] Prominent surface features include multi-ring structures, variously shaped impact craters, and chains of craters (catenae) and associated scarps, ridges and deposits.[13] At a small scale, the surface is varied and made up of small, sparkly frost deposits at the tips of high spots, surrounded by a low-lying, smooth blanket of dark material.[7] This is thought to result from the sublimation-driven degradation of small landforms, which is supported by the general deficit of small impact craters and the presence of numerous small knobs, considered to be their remnants.[14] The absolute ages of the landforms are not known. Callisto is composed of approximately equal amounts of rock and ice, with a density of about 1.83 g/cm3, the lowest density and surface gravity of Jupiter's major moons. Compounds detected spectroscopically on the surface include water ice,[15] carbon dioxide, silicates and organic compounds. Investigation by the Galileo spacecraft revealed that Callisto may have a small silicate core and possibly a subsurface ocean of liquid water[15] at depths greater than 100 km.[16][17]
It is not in an orbital resonance like the three other Galilean satellites—Io, Europa and Ganymede—and is thus not appreciably tidally heated.[18] Callisto's rotation is tidally locked to its orbit around Jupiter, so that it always faces the same direction, making Jupiter appear to hang directly overhead over its near-side. It is less affected by Jupiter's magnetosphere than the other inner satellites because of its more remote orbit, located just outside Jupiter's main radiation belt.[19][20] Callisto is surrounded by an extremely thin atmosphere composed of carbon dioxide[9] and probably molecular oxygen,[10] as well as by a rather intense ionosphere.[21] Callisto is thought to have formed by slow accretion from the disk of the gas and dust that surrounded Jupiter after its formation.[22] Callisto's gradual accretion and the lack of tidal heating meant that not enough heat was available for rapid differentiation. The slow convection in the interior of Callisto, which commenced soon after formation, led to partial differentiation and possibly to the formation of a subsurface ocean at a depth of 100–150 km and a small, rocky core.[23]
The likely presence of an ocean within Callisto leaves open the possibility that it could harbor life. However, conditions are thought to be less favorable than on nearby Europa.[24] Various space probes from Pioneers 10 and 11 to Galileo and Cassini have studied Callisto. Because of its low radiation levels, Callisto has long been considered the most suitable to base possible future crewed missions on to study the Jovian system.[25]
- ^ Cite error: The named reference
Galileiwas invoked but never defined (see the help page). - ^ "Callisto". Lexico UK English Dictionary. Oxford University Press. Archived from the original on 22 March 2020.
- ^ a b c d e Cite error: The named reference
orbitwas invoked but never defined (see the help page). - ^ a b c d Cite error: The named reference
Anderson 2001was invoked but never defined (see the help page). - ^ Schubert, G.; Anderson, J. D.; Spohn, T.; McKinnon, W. B. (2004). "Interior composition, structure and dynamics of the Galilean satellites". In Bagenal, F.; Dowling, T. E.; McKinnon, W. B. (eds.). Jupiter : the planet, satellites, and magnetosphere. New York: Cambridge University Press. pp. 281–306. ISBN 978-0521035453. OCLC 54081598. Archived from the original on 16 April 2023. Retrieved 23 July 2019.
- ^ a b c Archinal, B. A.; Acton, C. H.; A'Hearn, M. F.; Conrad, A.; Consolmagno, G. J.; Duxbury, T.; Hestroffer, D.; Hilton, J. L.; Kirk, R. L.; Klioner, S. A.; McCarthy, D.; Meech, K.; Oberst, J.; Ping, J.; Seidelmann, P. K. (2018). "Report of the IAU Working Group on Cartographic Coordinates and Rotational Elements: 2015". Celestial Mechanics and Dynamical Astronomy. 130 (3): 22. Bibcode:2018CeMDA.130...22A. doi:10.1007/s10569-017-9805-5. ISSN 0923-2958.
- ^ a b c Cite error: The named reference
Moore2004was invoked but never defined (see the help page). - ^ "Classic Satellites of the Solar System". Observatorio ARVAL. Archived from the original on 9 July 2011. Retrieved 13 July 2007.
- ^ a b c Cite error: The named reference
Carlson 1999was invoked but never defined (see the help page). - ^ a b Cite error: The named reference
Liang 2005was invoked but never defined (see the help page). - ^ "Callisto – Overview – Planets – NASA Solar System Exploration". NASA Solar System Exploration. Archived from the original on 28 March 2014.
- ^ Glenday, Craig (2013). Guinness Book of World Records 2014. Guinness World Records Limited. p. 187. ISBN 978-1-908843-15-9.
- ^ a b Cite error: The named reference
Greeley 2000was invoked but never defined (see the help page). - ^ Cite error: The named reference
Moore1999was invoked but never defined (see the help page). - ^ a b Chang, Kenneth (12 March 2015). "Suddenly, It Seems, Water Is Everywhere in Solar System". The New York Times. Archived from the original on 9 May 2020. Retrieved 12 March 2015.
- ^ Cite error: The named reference
Kuskov2005was invoked but never defined (see the help page). - ^ Showman, A. P.; Malhotra, R. (1 October 1999). "The Galilean Satellites". Science. 286 (5437): 77–84. doi:10.1126/science.286.5437.77. PMID 10506564. S2CID 9492520.
- ^ Cite error: The named reference
Musotto2002was invoked but never defined (see the help page). - ^ Cite error: The named reference
Cooper2001was invoked but never defined (see the help page). - ^ "Exploring Jupiter – JIMO – Jupiter Icy Moons Orbiter – the moon Callisto". Space Today Online. Archived from the original on 26 June 2018. Retrieved 11 October 2014.
- ^ Cite error: The named reference
Kliore 2002was invoked but never defined (see the help page). - ^ Cite error: The named reference
Canup2002was invoked but never defined (see the help page). - ^ Cite error: The named reference
Spohn 2003was invoked but never defined (see the help page). - ^ Cite error: The named reference
Lipps2004was invoked but never defined (see the help page). - ^ Cite error: The named reference
HOPEwas invoked but never defined (see the help page).
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