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Gwen Barnes

Gwen Barnes

Research Assistant Professor


Engineering-Physics 325


(208) 885-6809

Mailing Address

Department of Physics
University of Idaho
875 Perimeter Drive, MS 0903
Moscow, ID 83844-0903

  • Ph.D., Planetary Science, University of Arizona (UofA), Tucson, AZ, USA, May 2007.
  • B.S., Chemistry, University of California, Santa Barbara (UCSB), USA, Dec 1998.

Gwen studies the physical processes that shape the surfaces of the Moon and Mars.

I study impact cratering 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.

Please note that Gwen publishes under the last name Bart.

  • Bart, G.D., H.J. Melosh. (2010) Distributions of Boulders Ejected from Lunar Craters. Icarus, 209, 337-357, doi: 10.1016/j.icarus.2010.05.023.
  • Bart, G.D., H.J. Melosh. (2010) Impact Into Lunar Regolith Inhibits High Velocity Ejection of Large Blocks. J. Geophysical Research. 115, E08004, doi: 10.1029/2009JE003441l.
  • Bart, G.D., H.J. Melosh. (2007) Using Lunar Boulders to Distinguish Primary From Distant Secondary Impact Craters. Geophysical Research Letters, 34, L07203, doi: 10.1029/2007GL029306.
  • Bart, G.D. (2007) Comparison of Small Lunar Landslides and Martian Gullies. Icarus 187, 417-421, doi: 10.1016/j.icarus.2006.11.004.
  • Bart, G. D., E.P. Turtle, W.L. Jaeger, L.P. Keszthelyi, R. Greenberg. (2004) Ridges and Tidal Stress on Io. Icarus, 169, 111-126, doi: 10.1016/j.icarus.2004.01.003.


Department of Physics

Physical Address:
Engineering-Physics Rm 311

Mailing Address:
875 Perimeter Drive, MS 0903
Moscow, ID 83844-0903

Phone: (208) 885-6380

Fax: (208) 885-4055


Web: Department of Physics