Orbital Dynamics


Renu Malhotra
Renu Malhotra


Kepler's laws of planetary motion turn out to be far from the last word on planetary orbits. Orbits change over time, some changes are slow and periodic, others are chaotic and dramatic; these determine the architecture of planetary systems. In orbital dynamics research, we seek to discover the past and future of planetary systems - the diverse effects of gravity that shape where and how planets form and how their orbits evolve in time. We study the orbital evolution of planetary and satellite systems, and small bodies (asteroids and comets), as well as interplanetary dust, in the solar system and in exo-planetary systems. We seek discovery and understanding of the dynamical transport processes of planetary materials across vast distances in space and over geologically long times. We study how Earth's habitability is affected by its orbital history, and how orbital dynamics shapes extra-terrestrial environments.


  • Professor Renu Malhotra is serving on the Science Advisory Committee for the LSST. Read about her thoughts for solar system science with the LSST.
  • Some of the orbital dynamics group attended the AAS-Dynamical Astronomy Division annual meeting, April 28-May 1, in Philadelphia, PA. See Professor Malhotra's presentation titled, "A few points on the dynamical evolution of the young solar system."
  • Christa Van Laerhoven defended her Ph.D. dissertation, "Multi-Planet Extra-Solar Systems: Tides and Classical Secular Theory" on April 16, 2014. Congratulations, Dr. Van Laerhoven! She is currently a postdoctoral researcher at the University of Toronto.
  • Kathryn Volk defended her Ph.D. dissertation, "Dynamical Studies of the Kuiper Belt and the Centaurs", on April 01, 2013. Congratulations, Dr. Volk! She is presently the CITA National Fellow at the University of British Columbia.
  • College of Science awards Kathryn Volk "Outstanding Graduate Student - Scholarship", April 2013.
  • College of Science awards Galileo Circle Scholarship to Sarah Morrison, April 2013.


Robert G. Strom, Renu Malhotra, Zhiyong Xiao, Takashi Ito, Fumi Yoshida, and Lillian R. Ostrach, The inner solar system cratering record and the evolution of impactor populations, Research in Astronomy and Astrophysics, in press (2014). Preprint

JeongAhn, Y., Malhotra, R., On the Non-uniform Distribution of the Angular Elements of Near-Earth Objects, Icarus, 229:236-246 (2014).  Preprint.

Rodigas, T.J., Malhotra, R., Hinz, P.M., Predictions for Shepherding Planets in Scattered Light Images of Debris Disks, ApJ, 780, 65 (2014).  Preprint.

Su, K.Y.L., Rieke, G.H., Malhotra, R., et al., Asteroid belts in debris disk twins: Vega and Fomalhaut, ApJ, 763, 118 (2013).  Preprint.

Petrovich, C., Malhotra, R., Tremaine, S., Planets Near Mean-Motion Resonances, ApJ, 770, 24 (2013).  Preprint

Volk, K., Malhotra, R., Do Centaurs preserve their source inclinations?, Icarus, 224:66-73 (2013).

Malhotra, R., Orbital resonances in planetary systems. To appear in volume 6.119.55 CELESTIAL MECHANICS of the Encyclopedia of Life Support Systems by UNESCO. Preprint (Sep 2012)

Volk, K., Malhotra, R., The effect of orbital evolution on the Haumea (2003 EL61) collisional family, Icarus, 221:106-115 (2012).

Belbruno, E., A. Moro-Martin, R. Malhotra, D. Savransky, Chaotic Exchange of Solid Material between Planetary Systems: Implications for Lithopanspermia, Astrobiology, doi:10.1089/ast.2012.0825 (2012). Preprint