Mars Research

Introduction
Mars is the most Earth-like of the terrestrial planets: it has a (thin) atmosphere, large volcanoes which may be active, and intermittent flows of water on the surface. In the past it may have been dramatically different: the highlands still preserve traces of ancient bombardment by meteorites, and the lowlands may have possessed lakes or oceans. Because Mars is a potential habitat for life, it is being explored by numerous spacecraft: Mars Global Surveyor, Mars Odyssey and Mars Express are all currently active. The two Mars Pathfinders are still roving the surface and sending back data. Understanding the geological and climatological evolution of Mars is one of the biggest challenges facing the planetary science community.

Martian Interior
Mars once had a dynamo, like the Earth's, and may have had plate tectonics. Are these two facts related? Why does one half of Mars have a thicker crust than the other (rather like the Moon)? These questions, and others like them, are the focus of work by Nimmo, Asphaug and their graduate students, using a variety of geophysical models.

Martian Surface
Mars has a subsurface layer of water ice, and liquid water occasionally flows on the surface. How long can the liquid water survive? What happens to it once it freezes, and is there geological evidence for areas where this has happened? Asphaug and Tulacyzk are using a combination of MOC and Viking images and geological models to investigate these questions.

Martian Atmosphere
The sudden escape of large volumes of liquid water to the surface must have had a significant effect on the Martian climate. Conversely, where this water is ultimately deposited depends on the climate behavior. Sloan and Santiago are investigating these questions using a General Circulation Model developed in collaboration with NASA Ames Research Center.

Recent Publications

Authors	Title	Year	Source
Lyons, JR; Manning, C; Nimmo, F	Formation of methane on Mars by fluid-rock interaction in the crust	2005-7-1	GEOPHYSICAL RESEARCH LETTERS
Nimmo, F	Tectonic consequences of Martian dichotomy modification by lower-crustal flow and erosion	2005-7	GEOLOGY
Williams, JP; Nimmo, F	Thermal evolution of the Martian core: Implications for an early dynamo	2004-2	GEOLOGY
Nimmo, F	Admittance estimates of mean crustal thickness and density at the Martian hemispheric dichotomy	2002-11	JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
Nimmo, F; Stevenson, DJ	Estimates of Martian crustal thickness from viscous relaxation of topography	2001-3-25	JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS