Science Results from the Mars Exploration Rover Mission
Goldwin Smith Professor of Astronomy
Reception following the lecture in the Woods Atrium, Chemistry
The two Mars exploration rovers, Spirit and Opportunity, touched down on Mars in January 2004 and have been conducting extensive observations with the Athena science payload. Together the two rovers have traversed more than 40 km.
Spirit, located on the floor of Gusev crater, has investigated basaltic plains, as well as older materials in the Columbia Hills. The rocks of the Columbia Hills are granular in nature and have undergone significant alteration by water. They appear to be largely a mixture of altered impact ejecta and explosive volcanic materials. Spirit has discovered silica-rich deposits that may have formed in a hot spring or volcanic fumarole environment, as well as massive carbonate-rich rocks.
Opportunity has carried out the first outcrop-scale investigation of ancient sedimentary rocks on Mars. The rocks are sandstones formed by wind and water erosion and re-deposition of dirty evaporite materials rich in sulfate salts. The stratigraphic section is dominated by wind-blown bedforms, with water-formed current ripples exposed locally near the top of the section. While liquid water was present at Meridiani below and occasionally at the surface, the ancient environmental conditions recorded there are dominantly arid, acidic and oxidizing, and would have posed some significant challenges to life.
In the past year, Opportunity has investigated the rim of Endeavour Crater. Basaltic breccias produced by the impact form the rim deposits, with stratigraphy similar to that observed at similar-sized craters on Earth. Highly localized Zn enrichments in some breccia materials suggest hydrothermal alteration of rim deposits. Gypsum-rich veins cut sedimentary rocks adjacent to the crater rim. The gypsum was precipitated from low-temperature aqueous fluids flowing upward from the ancient materials of the rim, leading temporarily to potentially habitable conditions.
Steve Squyres is the Goldwin Smith Professor of Astronomy at Cornell University. His research focuses on the robotic exploration of planetary surfaces, the history of water on Mars, geophysics and tectonics of icy satellites, tectonics of Venus, planetary gamma-ray and x-ray spectroscopy. Research for which he is best known includes study of the history and distribution of water on Mars and of the possible existence and habitability of a liquid water ocean on Europa.
Dr. Squyres has participated in a number of planetary spaceflight missions. From 1978 to 1981 he was an associate of the Voyager imaging science team, participating in analysis of imaging data from the encounters with Jupiter and Saturn. He was a radar investigator on the Magellan mission to Venus, a member of the Mars Observer gamma-ray spectrometer flight investigation team, and a co-investigator on the Russian Mars 1996 mission. Dr. Squyres is currently the scientific Principal Investigator for the Mars Exploration Rover Project. He is also a co-investigator on the Mars Express mission, and on the Mars Reconnaissance Orbiter's High Resolution Imaging Science Experiment. He is a member of the Gamma-Ray Spectrometer Flight Investigation Team for the Mars Odyssey mission, and a member of the imaging team for the Cassini mission to Saturn.