Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-23T13:47:22.849Z Has data issue: false hasContentIssue false

Planetary Trojans – the main source of short period comets?

Published online by Cambridge University Press:  27 July 2010

J. Horner
Affiliation:
Department of Physics, Science Laboratories, University of Durham, South Road, Durham, UK, DH1 3LE
P. S. Lykawka
Affiliation:
Faculty of Applied Sociology (Astronomy branch), Kinki University, Shinkamikosaka 228-3, Higashiosaka-shi, Osaka, 577-0813, Japan

Abstract

One of the key considerations when assessing the potential habitability of telluric worlds will be that of the impact regime experienced by the planet. In this work, we present a short review of our understanding of the impact regime experienced by the terrestrial planets within our own Solar system, describing the three populations of potentially hazardous objects which move on orbits that take them through the inner Solar system. Of these populations, the origins of two (the Near-Earth Asteroids and the Long-Period Comets) are well understood, with members originating in the Asteroid belt and Oort cloud, respectively. By contrast, the source of the third population, the Short-Period Comets, is still under debate. The proximate source of these objects is the Centaurs, a population of dynamically unstable objects that pass perihelion (closest approach to the Sun) between the orbits of Jupiter and Neptune. However, a variety of different origins have been suggested for the Centaur population. Here, we present evidence that at least a significant fraction of the Centaur population can be sourced from the planetary Trojan clouds, stable reservoirs of objects moving in 1:1 mean-motion resonance with the giant planets (primarily Jupiter and Neptune). Focussing on simulations of the Neptunian Trojan population, we show that an ongoing flux of objects should be leaving that region to move on orbits within the Centaur population. With conservative estimates of the flux from the Neptunian Trojan clouds, we show that their contribution to that population could be of order ~3%, while more realistic estimates suggest that the Neptune Trojans could even be the main source of fresh Centaurs. We suggest that further observational work is needed to constrain the contribution made by the Neptune Trojans to the ongoing flux of material to the inner Solar system, and believe that future studies of the habitability of exoplanetary systems should take care not to neglect the contribution of resonant objects (such as planetary Trojans) to the impact flux that could be experienced by potentially habitable worlds.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2010

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Andrews-Hanna, J.C., Zuber, M.T., & Banerdt, W.B., 2008, Nature, 453, 1212.CrossRefGoogle Scholar
Bailey, B.L. & Malhotra, R., 2009, Icarus, 203, 155.CrossRefGoogle Scholar
Baldwin, E.C., Milner, D.J., Burchell, M.J., & Crawford, I.A., 2007, Meteoritics and Planetary Science, 42, 1905.CrossRefGoogle Scholar
Benz, W., Anic, A., Horner, J. & Whitby, J.A., 2007, Space Science Reviews, 132, 189.CrossRefGoogle Scholar
Biermann, L., Huebner, W.F., & Lust, R., 1983, Proceedings of the National Academy of Science, 80, 5151.CrossRefGoogle Scholar
Bottke, W.F., Morbidelli, A., Jedicke, R., Petit, J.-M., Levison, H.F., Michel, P., & Metcalfe, T.S., 2002, Icarus, 156, 399.CrossRefGoogle Scholar
Bottke, W., Vokrouhlický, D., Nesvorný, D., 2007, Nature, 448, 4853.CrossRefGoogle Scholar
Brasser, R., Mikkola, S., Huang, T.-Y., Wiegert, P., Innanen, K., 2004, MNRAS, 347, 833.CrossRefGoogle Scholar
Brett, R., 1992, Geochimica et Cosmochimica Acta, 56, 3603.CrossRefGoogle Scholar
Brunini, A., Melita, M.D., 2002, Icarus, 160, 32.CrossRefGoogle Scholar
Cabrol, N.A., et al. , 2006, Journal of Geophysical Research (Planets), 111, 2.Google Scholar
Calvin, W.M., et al. , 2008, Journal of Geophysical Research (Planets), 113, 12.Google Scholar
Chambers, J.E., 1999, MNRAS, 304, 793.CrossRefGoogle Scholar
Chapman, C.R., 1994, Nature 367, 3340.CrossRefGoogle Scholar
Chiang, E.I. et al. , 2003, AJ, 126, 430.CrossRefGoogle Scholar
Chiang, E.I., Lithwick, Y., 2005, ApJ, 628, 520.CrossRefGoogle Scholar
Chebotarev, G.A., 1974, SvA, 17, 677.Google Scholar
di Sisto, R.P., Brunini, A., 2007, Icarus, 190, 224.CrossRefGoogle Scholar
Edgeworth, K.E., 1943, Journal of the British Astronomical Association, 53, 181.Google Scholar
Emel'yanenko, V.V., Asher, D.J., & Bailey, M.E., 2005, MNRAS, 361, 1345.CrossRefGoogle Scholar
Emel'Yanenko, V.V., Asher, D.J., & Bailey, M.E., 2007, MNRAS, 381, 779.CrossRefGoogle Scholar
Fernandez, J.A., Ip, W.-H., 1984, Icarus, 58, 109.CrossRefGoogle Scholar
Ford, E.B., Chiang, E.I., 2007, ApJ, 661, 602.CrossRefGoogle Scholar
Fouchard, M., Froeschlé, C., Matese, J.J., & Valsecchi, G., 2005, Celestial Mechanics and Dynamical Astronomy, 93, 229.CrossRefGoogle Scholar
Glasby, G.P. & Kunzendorf, H. 1996, Geologische Rundschau, 85, 191.CrossRefGoogle Scholar
Gomes, R.S., Morbidelli, A., Levison, H.F., 2004, Icarus, 170, 492.CrossRefGoogle Scholar
Gomes, R., Levison, H.F., Tsiganis, K., Morbidelli, A., 2005, Natures, 435, 466469.CrossRefGoogle Scholar
Grant, J.A., et al. , 2008, Geology, 36, 195.CrossRefGoogle Scholar
Hahn, J.M., Malhotra, R., 2005, AJ, 130, 2392.CrossRefGoogle Scholar
Heisler, J., & Tremaine, S. 1986, Icarus, 65, 13.CrossRefGoogle Scholar
Holman, M.J., Wisdom, J., 1993, AJ, 105, 1987.CrossRefGoogle Scholar
Horner, J. & Evans, N.W., 2002, MNRAS, 335, 641.CrossRefGoogle Scholar
Horner, J., Evans, N.W., Bailey, M.E. & Asher, D.J., 2003, MNRAS 343, 10571066.CrossRefGoogle Scholar
Horner, J., Evans, N.W. & Bailey, M.E., 2004a, MNRAS 354, 798810.CrossRefGoogle Scholar
Horner, J., Evans, N.W. & Bailey, M.E., 2004b, MNRAS, 355, 321.CrossRefGoogle Scholar
Horner, J., & Wyn Evans, N., 2006, MNRAS, 367, L20.CrossRefGoogle Scholar
Horner, J. & Jones, B.W., 2010, International Journal of Astrobiology (submitted)Google Scholar
Horner, J. & Lykawka, P.S., 2010a, MNRAS, 402, 13.CrossRefGoogle Scholar
Horner, J. & Lykawka, P.S., 2010b, MNRAS, 441.Google Scholar
Ivezic, Z. et al. , 2008, preprint (astro-ph/0805.2366) (http://www.lsst.org/overview)Google Scholar
Jewitt, D.C., 2003, Earth Moon Planets, 92, 465.Google Scholar
Kuiper, G.P., 1951, Astrophysics: A Topical Symposium, ed. Hynek, J.A., New York: McGraw-Hill.Google Scholar
Levison, H.F., & Duncan, M.J., 1997, Icarus, 127, 13.CrossRefGoogle Scholar
Levison, H.F., Morbidelli, A., Vanlaerhoven, C., Gomes, R., Tsiganis, K., 2008, Icarus, 196, 258.CrossRefGoogle Scholar
Lykawka, P.S., Mukai, T., 2007, Icarus, 189, 213.CrossRefGoogle Scholar
Lykawka, P.S., Mukai, T., 2008, AJ, 135, 1161.CrossRefGoogle Scholar
Lykawka, P.S., Horner, J., Jones, B.W. & Mukai, T., 2009, MNRAS, 398, 1715.CrossRefGoogle Scholar
Lykawka, P.S., Horner, J., Jones, B.W. & Mukai, T., 2010, MNRAS, 296.Google Scholar
Lykawka, P.S. & Horner, J., 2010, MNRAS, 513.Google Scholar
Malhotra, R., 1995, AJ, 110, 420.CrossRefGoogle Scholar
Marzari, F., Tricarico, P., Scholl, H., 2003, A&A, 410, 725.Google Scholar
Matese, J.J., Whitman, P.G. & Whitmire, D.P., 1999, Icarus, 141, 354.CrossRefGoogle Scholar
Matese, J.J. & Whitmire, D.P., 2010, arXiv:1004.4584Google Scholar
Mazeeva, O.A., 2004, Solar System Research, 38, 325.CrossRefGoogle Scholar
Mikkola, S., Innanen, K., 1992, AJ, 104, 1641.CrossRefGoogle Scholar
Milner, D.J., Baldwin, E.C., & Burchell, M.J., 2008, Meteoritics and Planetary Science, 43, 2015.CrossRefGoogle Scholar
Morbidelli, A., Bottke, W.F., Froeschlé, Ch. & Michel, P., 2002, Origin and Evolution of Near-Earth Objects, Asteroids III, University of Arizona Press, Tucson, AZ, pp. 409422.Google Scholar
Mueller, T.G. et al. , 2009, EM&P, 29.Google Scholar
Murray, C.D., Dermott, S.F., 1999, Solar System Dynamics, Princeton Univ. Press, Princeton, NJ.Google Scholar
Murray, J.B., 1999, MNRAS, 309, 31.CrossRefGoogle Scholar
Nesvorný, D., Dones, L., 2002, Icarus, 160, 271.CrossRefGoogle Scholar
Oort, J.H. (1950). The structure of the cloud of comets surrounding the Solar System, and a hypothesis concerning its origin, Bull. Astron. Inst. Ned., 11(408), 91–110.Google Scholar
Poinar, G.O. & Poinar, R., 2008, What bugged the dinosaurs?: insects, disease, and death in the Cretaceous, Princeton: Princeton University Press.Google Scholar
Sheppard, S.S., Trujillo, C.A., 2006, Sci, 313, 511.CrossRefGoogle Scholar
Tedesco, E.F., Desert, F.-X., 2002, AJ, 123, 2070.CrossRefGoogle Scholar
Thaddeus, P. & Chanan, G.A., 1985, Nature, 314, 73.CrossRefGoogle Scholar
Tiscareno, M.S., Malhotra, R., 2003, AJ, 126, 3122.CrossRefGoogle Scholar
Volk, K., & Malhotra, R., 2008, Astrophysical Journal, 687, 714.CrossRefGoogle Scholar