Hostname: page-component-7bb8b95d7b-cx56b Total loading time: 0 Render date: 2024-09-21T10:08:30.505Z Has data issue: false hasContentIssue false
  • English
  • Français

Radar Contributions to Asteroid Astrometry and Dynamics

Published online by Cambridge University Press:  12 April 2016

Steven J. Ostro
Steven J. Ostro*
Affiliation:
Jet Propulsion Laboratory, California Institute of Technology Pasadena, California, USA

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Almost every radar observation of asteroids has measured some characteristics of the distribution of echo power in time delay (range) and Doppler frequency (radial velocity). Such measurements, which are orthogonal to optical plane-of-sky angular astrometry, are also done in the well-known, “absolute” reference frame of the planetary ephemerides, often with fractional precision that is much finer than can be achieved with other kinds of groundbased observations; they therefore can dramatically refine orbits and ephemerides. This statement is most true for near-Earth asteroids (NEAs), which constitute the most prolifically observed radar targets and are likely to be observed in increasing abundance as instrumental capabilities improve and CCD-based, NEA search programs expand. Moreover, studies of closely approaching NEAs benefit tremendously from the inverse fourthpower dependence of echo strength on target distance. For these reasons, I devote the bulk of this paper to NEAs

Type
Dynamics and Astrometry: Present and Future
Information
International Astronomical Union Colloquium , Volume 165: Dynamics and Astrometry of Natural and Artificial Celestial Bodies , 1997 , pp. 87 - 96
Copyright
Copyright © Kluwer 1997

References

Asphaug, E., Ostro, S.J., de Jong, E.M., Scheeres, D.J., Suzuki, S., Hudson, R.S., and Benz, W.: 1996, “Disruptive impacts into an Earth-approaching asteroid”, Bull. Am. Astron. Soc, in press.Google Scholar
de Pater, I., Palmer, P., Mitchell, D.L., Ostro, S.J., Yeomans, D.K., and Snyder, L.E.: 1994, “Radar aperture synthesis observations of asteroids”, Icarus 111, 489–502.CrossRefGoogle Scholar
Hudson, R.S.: 1993, “Three-dimensional reconstruction of asteroids from radar observations”, Remote Sensing Reviews 8, 195–203.CrossRefGoogle Scholar
Hudson, R.S. and Ostro, S.J.: 1994, “Shape of asteroid 4769 Castalia (1989 PB) from inversion of radar images”, Science 263, 940–943.CrossRefGoogle ScholarPubMed
Hudson, R.S. and Ostro, S.J.: 1995, “Shape and non-principal axis spin state of asteroid 4179 Toutatis”, Science 270, 84–86.Google Scholar
Hudson, R.S. and Ostro, S.J.: 1995, “Radar-based physical models of Earth-crossing asteroids”, Bull. Am. Astron. Soc. 27, 1062.Google Scholar
Ostro, S.J.: 1993, “Planetary radar astronomy”, Rev. Mod. Phys. 65, 1235–1279.CrossRefGoogle Scholar
Ostro, S.J.: 1994, “The role of groundbased radar in near-Earth object hazard identification and mitigation”, in: Hazards Due to Comets and Asteroids (Gehrels, T., Matthews, M.S., eds), Univ. of Arizona Press, 259–282.Google Scholar
Ostro, S.J., Campbell, D.B., Chandler, J.F., Shapiro, I.I., Hine, A.A., Velez, R., Jurgens, R.F., Rosema, K.D., Winkler, R., and Yeomans, D.K.: 1991, “Asteroid radar astrometry”, Astron. J. 102, 1490–1502.Google Scholar
Ostro, S.J., Hudson, R.S., Jurgens, R.F., Rosema, K.D., Winkler, R., Howard, D., Rose, R., Slade, M.A., Yeomans, D.K., Giorgini, J.D., Campbell, D.B., Perillat, P., Chandler, J.F., and Shapiro, I.I.: 1995, “Radar images of asteroid 4179 Toutatis”, Science 270, 80–83.CrossRefGoogle Scholar
Ostro, S.J., Rosema, K.D., Hudson, R.S., Jurgens, R.F., Giorgini, J.D., Winkler, R., Yeomans, D.K., Choate, D., Rose, R., Slade, M.A., Howard, S.D., and Mitchell, D.L.: 1995, “Extreme elongation of asteroid 1620 Geographos from radar images”, Nature 375, 474–477.Google Scholar
Ostro, S.J., Choate, D., Cormier, R.A., Franck, C.R., Frye, R., Giorgini, J., Howard, D., Jurgens, R.F., Littlefair, R., Mitchell, D.L., Rose, R., Rosema, K.D., Slade, M.A., Strobert, D.R.,, Winkler, R., Yeomans, D.K., Hudson, R.S., Palmer, P., Snyder, L.E., Zaitsev, A., Ignatov, S., Koyama, Y., and Nakamura, A.: 1995, “Asteroid 1991 JX: The 1995 Goldstone radar experiment”, Bull. Am. Astron. Soc. 27, 1063.Google Scholar
Ostro, S.J., Jurgens, R.F., Rosema, K.D., Hudson, R.S., Giorgini, J.D., Winkler, R., Yeomans, D.K., Scheeres, D.J., Choate, D., Rose, R., Slade, M.A., Howard, S.D., and Mitchell, D.L.: 1996, “Radar images of Geographos”, Icarus 121, 44–66.Google Scholar
Scheeres, D.J., Ostro, S.J., Hudson, R.S., and Werner, R.A.: 1996, “Orbits close to asteroid 4769 Castalia”, Icarus 121, 67–87.CrossRefGoogle Scholar
Werner, R.A.: 1994, “The gravitational potential of a homogeneous polyhedron”, Celest. Mech. & Dyn. Astron. 59, 253–278.Google Scholar
Yeomans, D.K., Ostro, S.J., and Chodas, P.W.: 1987, “Radar astrometry of near-Earth asteroids”, Astron. J. 94, 189–200.CrossRefGoogle Scholar
Yeomans, D.K., Chodas, P.W., Keesey, M.S., Ostro, S.J., Chandler, J.F., and Shapiro, I.I.: 1992, “Asteroid and comet orbits using radar data”, Astron. J. 103, 303–317.CrossRefGoogle Scholar
Yeomans, D.K. and Chodas, P.W.: 1994, “Predicting close approaches of asteroids and comets to Earth”, in: Hazards Due to Comets and Asteroids (T.Gehrels, Matthews, M.S., eds), Univ. of Arizona Press, 241–258.Google Scholar