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Tue December 11, 2012
Dr. Stuart Robbins, University of Colorado, Boulder – Mapping Martian Craters
In today’s Academic Minute, Dr. Stuart Robbins of the University of Colorado Boulder explains his work mapping craters on the surface of Mars.
Stuart Robbins is a postdoctoral researcher in astronomy at the University of Colorado, Boulder. His current work is focused on managing and finding applications for his Mars global crater database at the Laboratory for Atmospheric and Space Physics (LASP) at CU-Boulder. He also maintains a blog entitled Exposing PseudoAstronomy and produces a regular podcast also focused on exposing pseudoastronomy.
Dr. Stuart Robbins – Mapping Martian Craters
Impact craters form one of the most common surface features across the solar system, but we don't often think about them on Earth because we have an active planet that recycles the crust. When we study other worlds, understanding impact craters is a key part.
One of my research philosophies is that if you're going to do something, do it all. Following that, I spent five years literally drawing circles - identifying over 640,000 craters on the planet Mars to get a complete census of all of the ones larger than a kilometer across. Analyzing that database has just begun, but we're already learning a lot of things that weren't possible before because people had done smaller, more limited studies.
One application is that we're better understanding how old different parts of Mars and features on the surface are: The way this works is that if a surface has been around longer, it should have more craters on it. We use that along with models to determine the ages.
A complication to this is the phenomenon of secondary craters: Craters that form from large blocks ejected when another crater forms. We have to somehow remove secondary craters from the population of primary craters, otherwise, we'll get an artificially old age. This large Martian crater database that I put together is helping us to unravel how secondary craters manifest, and it's leading to many important discoveries.
These are just two applications of this vast catalog that should prove a useful resource for many researchers for many years to come.