One of the most fundamental questions in
planetary science today is the nature of the ambient climate
of early Mars (Noachian-Early Hesperian): Was the ambient
climate "warm and wet/arid", as suggested by widespread
phyllosilicates, higher erosion rates, enhanced crater
degradation, valley networks, and open/closed-basin lakes? Or
was the ambient climate "cold and icy", as suggested by recent
climate models, with occasional perturbations causing heating
and melting of surface snow and ice, and runoff to produce the
observed characteristics and features? Using the framework of
these two ambient climate options, we will discuss how the
NASA Mars 2020 Perseverance Rover mission at Jezero Crater
open-basin lake, and the CNSA Tianwen-1 Zhurong rover mission
to Utopia Planitia will help to resolve these issues.
About the Speaker:
James W. Head III is the Louis and
Elizabeth Scherck Distinguished Professor in the Department of
Earth, Environmental and Planetary Sciences at Brown
University. He earned an undergraduate degree from Washington
and Lee University (BS, 1964) and received his PhD from Brown
University in 1969. From 1968 to 1972, while serving at NASA
Headquarters (Bellcomm, Inc.), he participated in the
selection of landing sites for the Apollo program, in training
Astronaut crews in geology and surface exploration, in
planning and evaluating the package of experiments to be
deployed on the Moon, in mission operations in Houston during
lunar surface exploration, and in preliminary analysis of the
lunar samples returned by the Astronauts. For these activities
he received the NASA Medal for Exceptional Scientific
Achievement and the Geological Society of America Special
Commendation. He continues to be involved in training of the
NASA Astronauts. He has been elected to Fellowship in the
American Academy of Arts and Sciences, the American
Association for the Advancement of Science, the American
Geophysical Union, the Geological Society of America, and the
Meteoritical Society, and President of the Planetary Geology
Division of the GSA and Planetology Section of the AGU.
National and International space mission involvement includes
Soviet Venera 15/16 and Phobos, Russian Mars 1996, Luna and
PSRM and the US Magellan (Venus), Galileo (Jupiter), Mars
Global Surveyor, Moon Mineralogy Mapper experiment on the
Chandrayaan-1, MESSENGER (Mercury), GRAIL (Moon) and Space
Shuttle missions. He is presently participating in the US
lunar laser altimeter (LOLA) on Lunar Reconnaissance Orbiter
mission, and the European Space Agency's Mars Express mission.