2002-2003 Colloquium Series
NAU Physical Sciences (Bldg 19, Rm 321), Friday, 17 January 2003, 4:00 PM
(Refreshments at 3:45 PM)
ASTROBIOLOGY GOLLOQUIUM
Impact Craters as Indicators of Water on Mars
Nadine Barlow , Northern Arizona University
Abstract
Fresh Martian impact craters display a distinctive ejecta morphology,
which is believed to result from heating and vaporization of subsurface
volatiles during crater formation. Different types of ejecta
morphologies may provide clues to target characteristics, such as
layered materials and the physical state of the volatiles (ice versus
liquid). Our team has recently completed an analysis of the regional
variations in the different types of ejecta morphologies. Ejecta
morphologies believed to result from impact into ice-rich target
material are found globally on Mars. However, those morphologies
believed to be due to impact into layered targets or to excavation into
liquid-rich reservoirs are concentrated in specific regions of the
planet which show interesting correlations with the recent detection of
near-surface ice from the Mars Odyssey mission's Gamma Ray Spectrometer.
Dr. Nadine Barlow is an Assistant Professor in the Department of Physics
and Astronomy at Northern Arizona University. She received her PhD in
Planetary Sciences from the University of Arizona. Prior to coming to NAU,
she worked at the Lunar and Planetary Institute and NASA Johnson Space Center
(both in Houston, TX) and at the University of Central Florida in Orlando
where she developed the astronomy program and served as director of the UCF
Robinson Observatory. Her research interests include the evolution of the
impact record over the age of the solar system, the geologic evolution of
solid surfaced bodies, and the determination of surface properties on other
worlds. Her current research focuses on the use of Martian impact craters to
determine the distribution of subsurface volatile reservoirs. She also is a
member of the team proposing the Gusev impact crater as a landing site for
the 2003 Mars Exploration Rovers.
Local Host: Dave Koerner, (928) 523-4562.