Abstract
Irregular satellites have eccentric orbits that can be highly inclined or even retrograde relative to the equatorial planes of their planets. These objects cannot have formed by circumplanetary accretion, unlike the regular satellites that follow uninclined, nearly circular and prograde orbits1. Rather, they are probably products of early capture from heliocentric orbits2,3,4,5. Although the capture mechanism remains uncertain, the study of irregular satellites provides a window on processes operating in the young Solar System. Families of irregular satellites recently have been discovered around Saturn (thirteen members, refs 6, 7), Uranus (six, ref. 8) and Neptune (three, ref. 9). Because Jupiter is closer than the other giant planets, searches for smaller and fainter irregular satellites can be made. Here we report the discovery of 23 new irregular satellites of Jupiter, so increasing the total known population to 32. There are five distinct satellite groups, each dominated by one relatively large body. The groups were most probably produced by collisional shattering of precursor objects after capture by Jupiter.
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References
Peale, S. Origin and evolution of the natural satellites. Annu. Rev. Astron. Astrophys. 37, 533–602 (1999)
Kuiper, G. On the origin of the satellites and the Trojans. Vistas Astron. 2, 1631–1666 (1956)
Colombo, G. & Franklin, F. On the formation of the outer satellite groups of Jupiter. Icarus 15, 186–189 (1971)
Pollack, J., Burns, J. & Tauber, M. Gas drag in primordial circumplanetary envelopes: A mechanism for satellite capture. Icarus 37, 587–611 (1979)
Heppenheimer, T. & Porco, C. New contributions to the problem of capture. Icarus 30, 385–401 (1977)
Gladman, B. et al. Discovery of 12 satellites of Saturn exhibiting orbital clustering. Nature 412, 163–166 (2001)
Sheppard, S. et al. Satellites of Jupiter and Saturn. IAU Circ. No. 8116 (2003)
Gladman, B. et al. The discovery of Uranus XIX, XX and XXI. Icarus 147, 320–324 (2000)
Holman, M. et al. Satellites of Neptune. IAU Circ. No. 8047 (2003)
Sheppard, S., Jewitt, D., Fernandez, Y., Magnier, E. & Marsden, B. Satellites of Jupiter. IAU Circ. No. 7555 (2001)
Sheppard, S., Jewitt, D., Kleyna, J., Marsden, B. & Jacobson, R. Satellites of Jupiter. IAU Circ. No. 7900 (2002)
Pollack, J. et al. Formation of the giant planets by concurrent accretion of solids and gas. Icarus 124, 62–85 (1996)
Boss, A., Wetherill, G. & Haghighipour, N. Rapid formation of ice giant planets. Icarus 156, 291–295 (2002)
Carruba, V., Burns, J., Nicholson, P. & Gladman, B. On the inclination distribution of the Jovian irregular satellites. Icarus 158, 434–449 (2002)
Cruikshank, D. Radii and albedos of four trojan asteroids and Jovian satellites 6 and 7. Icarus 30, 224–230 (1977)
Gehrels, T. in Comets, Asteroids, Meteorites (ed. Delsemme, A.) 323–326 (Univ. Toledo Press, Toledo, 1977)
Tanga, P. et al. On the size distribution of asteroid families: The role of geometry. Icarus 141, 65–78 (1999)
Dohnanyi, J. Collisional models of asteroids and their debris. J. Geophys. Res. 74, 2531–2554 (1969)
Cellino, A., Zappala, V. & Farinella, P. The size distribution of mainbelt from IRAS data. Mon. Not. R. Astron. Soc. 253, 561–574 (1991)
Kessler, D. Derivation of the collision probability between orbiting objects: The lifetimes of Jupiter's outer moons. Icarus 48, 39–48 (1981)
Rettig, T., Walsh, K. & Consolmagno, G. Implied evolutionary differences of the Jovian irregular satellites from a BVR colour survey. Icarus 154, 313–320 (2001)
Thomas, P. et al. Impact excavation on asteroid 4 Vesta: Hubble Space Telescope results. Science 277, 1492–1495 (1997)
Melosh, H. Impact Cratering a Geologic Process 46–86 (Oxford Univ. Press, Oxford, 1989)
Nakamura, T. & Yoshikawa, M. Close encounters and collisions of short-period comets with Jupiter and its satellites. Icarus 116, 113–130 (1995)
Hartmann, W., Ryder, G., Dones, L. & Grinspoon, D. in Origin of the Earth and Moon (eds Canup, R. & Righter, K.) 493–512 (Univ. Arizona Press, Tucson, 2000)
Thommes, E., Duncan, M. & Levison, H. The formation of Uranus and Neptune among Jupiter and Saturn. Astron. J. 123, 2862–2883 (2002)
Sheppard, S. et al. Satellites of Jupiter. IAU Circ. No. 8089 (2003)
Saha, P. & Tremaine, S. The orbits of the retrograde Jovian satellites. Icarus 106, 549–562 (1993)
Acknowledgements
We thank Y. Fernandez for help with the observations. The Canada–France–Hawaii telescope is operated by the National Research Council of Canada, Le Centre National de la Recherche Scientifique de France, and the University of Hawaii. This work was supported by a grant to D.C.J. from NASA.
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Sheppard, S., Jewitt, D. An abundant population of small irregular satellites around Jupiter. Nature 423, 261–263 (2003). https://doi.org/10.1038/nature01584
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DOI: https://doi.org/10.1038/nature01584
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