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Steve Chesley

Senior Research Scientist

About

Education

  • Ph.D., Aerospace Engineering, University of Texas, Austin (1998)
  • M.S., Aerospace Engineering, Texas A&M University (1993)
  • B.S., Aerospace Engineering, Texas A&M University (1986)

Research Interests

  • Precision orbit estimation and trajectory prediction for asteroids and comets
  • Yarkovsky effect on asteroids
  • Comet nongravitational acceleration modeling
  • Asteroid impact hazard assessment
  • Asteroid deflection strategy

Experience

Professional Experience

  • Jet Propulsion Laboratory (2000-Present)
    • Senior Research Scientist (2014-Present)
    • Principal Engineer (2008-Present)
    • Senior Engineer (2000-2008)
  • NSF-NATO Postdoctoral Research Fellow, Univ. Pisa, Italy (1998-1999)
  • Doctoral Candidate, University of Texas, Austin, Texas (1993-1998)
  • Masters Candidate, Texas A&M University, College Station, Texas (1991-1993)
  • Pilot, United States Air Force (1986-1991)

Achievements

Awards & Recognitions

Publications

  1. S.R. Chesley et al., “The Trajectory Dynamics of Near-Earth Asteroid 101955 (1999 RQ36),” Icarus, in press, 2014.
  2. D. Farnocchia, S.R. Chesley et al., “Yarkovsky-driven impact risk analysis for asteroid (99942) Apophis,” Icarus, in press, 2013.
  3. D. Farnocchia, S.R. Chesley et al., “Near-Earth Asteroids with measurable Yarkovsky effect,” Icarus, in press, 2013.
  4. S.R. Chesley, et al., “An updated rotation model for Comet 9P/Tempel 1,” Icarus 222 pp.516-525, 2013.
  5. J. Baer, S.R. Chesley and R.D. Matson “Astrometric Masses of 26 Asteroids and Observations on Asteroid Porosity” AJ 141 pp. 143-154, 2011.
  6. J. Baer, S.R. Chesley and A. Milani “Development of an Observational Error Model” Icarus 212 pp. 438-447, 2011.
  7. S.R. Chesley, J. Baer and D.G. Monet “Treatment of star catalog biases in asteroid astrometric observations” Icarus 210(1), pp. 158-181, 2010.
  8. A. Milani, S.R. Chesley et al. “Long term impact risk for (101955) 1999 RQ36” Icarus 203(2) pp. 460-471, 2009.
  9. S. Chesley “The Quest to Find the Next Killer Asteroid – Before it Finds Us” The Planetary Report 29(2) March 2009.
  10. P. Jenniskens et al. “The impact and recovery of 2008 TC3” Nature 458, pp. 485- 488, 2009.
  11. D. Vokrouhlicky, S.R. Chesley and R.D. Matson “Orbital Identification for Asteroid 152563 (1992 BF) Through the Yarkovsky Effect” AJ 135, pp. 2336-2340, 2008.
  12. J. Baer, S.R. Chesley "Astrometric masses of 21 asteroids, and an integrated asteroid ephemeris" Celestial Mechanics and Dynamical Astronomy 100(1), pp. 27- 42, 2008.
  13. S.R. Chesley and S.N. Ward, "A Quantitative Assessment of the Human and Economic Hazard from Impact-generated Tsunami" Journal of Natural Hazards 38(3), pp. 355-374, 2006.
  14. S.R. Chesley, "Potential Impact Detection for Near-Earth Asteroids: The Case of 99942 Apophis (2004 MN4)", in Asteroids Comets, Meteors, Proceedings of IAU Symposium # 229 (D. Lazzaro, S. Ferraz-Mello and J.A. Fernandez, Eds.) pp. 215- 228, Cambridge Univ. Press, 2006.
  15. A. Milani, S.R. Chesley et al., "Nonlinear Impact Monitoring: Line Of Variations Searches for Impactors" Icarus 173(1), 362-384, 2005.
  16. S.R. Chesley and D.K. Yeomans, "Nongravitational Accelerations on Comets" in Dynamics of Populations of Planetary Systems, Proceedings of IAU Colloquium #197, held 31 August - 4 September, 2004 in Belgrade, Serbia and Montenegro. Edited by Z. Knezevic and A. Milani. Cambridge: Cambridge University Press, p.289-302, 2005.
  17. S.R. Chesley, "Very short arc orbit determination: the case of asteroid 2004 FU162" in Dynamics of Populations of Planetary Systems, Proceedings of IAU Colloquium #197, held 31 August - 4 September, 2004 in Belgrade, Serbia and Montenegro. Edited by Z. Knezevic and A. Milani. Cambridge: Cambridge University Press, p.255-258, 2005.
  18. S.R. Chesley and T.B. Spahr, "Earth impactors: Orbital characteristics and warning times," in Mitigation of Hazardous Comets and Asteroids, Eds. M.J.S. Belton et al., Cambridge University Press, pp. 22-37, 2004.
  19. S.R. Chesley et al. "Direct Detection of the Yarkovsky Effect by Radar Ranging to Asteroid 6489 Golevka" Science 302, 1739-1742, 2003.
  20. A. Milani, S.R. Chesley, P.W. Chodas and G.B. Valsecchi, "Asteroid Close Approaches: Analysis and Potential Impact Detection" in Asteroids III, Space Science Series, Univ. Arizona Press, pp. 55-69, 2002.
  21. S.R. Chesley et al., "Quantifying the risk posed by potential Earth impacts" Icarus 159(2), 423-432, 2002.
  22. D. Vokrouhlicky, S.R. Chesley and A. Milani, "On the observability of radiation forces acting on near-Earth asteroids" Celest. Mech. Dynam. Astron. 81, 149-165, 2001.
  23. D. Vokrouhlicky, A. Milani and S. R. Chesley, "Yarkovsky effect on small near-Earth asteroids: Mathematical formulation and examples." Icarus 148(1), 118-138, 2000.
  24. A. Milani, S.R. Chesley, and G.B. Valsecchi, "Asteroid Close Encounters with Earth: Risk Assessment." Planet. Space Sci. 48(10) 945-954, 2000.
  25. A. Milani, S.R. Chesley, A. Boattini and G.B. Valsecchi, "Virtual Impactors: Search and Destroy." Icarus 145(1), 12-24, 2000.
  26. A. Milani, S.R. Chesley, and G.B. Valsecchi, "Close approaches of asteroid 1999 AN10: Resonant and non-resonant returns." Astronomy & Astrophysics 346, L65- L68, 1999.
  27. S. Chesley and K. Zare, "Bifurcations in the mass ratio of the planar isosceles three-body problem." in Dynamics of Small Bodies in the Solar System (A. E. Roy and B. A. Steves, Eds.) 413-424, Kluwer, 1999.
  28. S. Chesley, "A global analysis of the generalized Sitnikov problem." Celest. Mech. Dynam. Astron. 73, 291-302, 1999.
  29. K. Zare and S. Chesley, "Order and chaos in the planar isosceles three-body problem." CHAOS 8(2), 475-494, 1998.