Impact Craters on the Moon and Mars.

My martian project is designed to understand the difference (if any) in the characteristics of ejecta from primary vs secondary craters. Primary craters are formed by a piece of interplanetary material impacting the surface at high velocities (10 km/s or so). Secondary craters are formed by ejecta from a large crater that is traveling so fast that when it impacts the surface it also forms an impact crater. This study should have implications for understanding the ages of planetary surfaces as determined by crater counting.

I also have a lunar project that studies a similar primary vs secondary crater problem.

Finally, I study the depth of the lunar regolith by analyzing the size distributions of craters with specific morphologies that indicate the regolith depth.

I also have a couple of pending projects: One is for continuing the regolith depth study; the other is for studying lunar landslide features.

Download CV (pdf)


Find my publications under the name G.D. BART.

Peer-reviewed publications.

Abstracts for conference presentations.

9 Bart, G. D., "The Quantitative Relationship Between Small Impact Crater Morphology and Regolith Depth", Icarus (2013), pp. submitted.
8 Bart, G. D. and Nickerson, R.D. and Lawder, M.T. and Melosh, H.J., "Global survey of lunar regolith depths from LROC images", Icarus 215 (2011), pp. 485-490.
7 Bart, G.D. and Melosh, H.J., "Distributions of boulders ejected from lunar craters", Icarus 209 (2010), pp. 337-357.
6 Bart, G.D. and Melosh, H.J., "Impact into lunar regolith inhibits high-velocity ejection of large blocks", J.Geophys. Res. 115 (2010), pp. E08004.
5 Colaprete, A. and Schultz, P. and Heldmann, J. and Wooden, D. and Shirley, M. and Ennico, K. and Hermalyn, B. and Marshall, W. and Ricco, A. and Elphic, R.C. and Goldstein, D. and Summy, D. and Bart, G.D. and Asphaug, E. and Korycansky, D. and Landis, D. and Sollitt, L., "Detection of Water in the LCROSS Ejecta Plume", Science 330 (2010), pp. 463-468.
4 Bart, G.D., "Comparison of small lunar landslides and martian gullies", Icarus 187 (2007), pp. 417-421.
3 Bart, G.D. and Melosh, H.J., "Using lunar boulders to distinguish primary from distant secondary impact craters", Geophys. Res. Lett. 34 (2007), pp. L07203.
2 Bart, G.D. and Turtle, E.P. and Jaeger, W.L. and Keszthelyi, L.P. and Greenberg, R., "Ridges and tidal stress on Io", Icarus 169 (2004), pp. 111-126.
1 Greenberg, R. and Hoppa, G.V. and Bart, G. and Hurford, T., "Tidal Stress Patterns on Europa's Crust", Celestial Mechanics and Dynamical Astronomy 87 (2003), pp. 171-188.


LASER: Lunar Advanced Science and Exploration Research, NASA
Principal Investigator (PI): G.D. Bart Collaborator: H.J. Melosh
Title: Lunar Surface Structure and Age from Impact Crater Analysis

MDAP: Mars Data Analysis Program, NASA
Principal Investigator (PI): G.D. Bart Collaborators: Alfred McEwen, Ingrid Daubar
Title: Martian Surface Structure and Age from Impact Crater Analysis


My office is in room 325 of the Engineering/Physics building at the University of Idaho.

Mailing Address

Gwen Barnes
Dept. of Physics, Univ. of Idaho
845 Perimeter Drive, MS 0903
Moscow, ID 83843

Email & Phone

gbarnes (at)