ABSTRACT

The Curiosity rover has been systematically exploring for more than 10 years the rocks and soils in an ancient martian crater that once contained a long-lived lake. The exploration of the past habitability of this site on Mars is a major goal of the mission. Over the course of the mission, to date, the Sample Analysis at Mars (SAM) instrument suite on the Curiosity rover has enabled a range of geochemical investigations including: (1) atmospheric composition (including methane) and its seasonal variation, (2) isotopic composition of gases in the present atmosphere and gases released from solid samples, (3) dating of rock formation ages using K/Ar measurements, (4) cosmic radiation exposure ages from noble gases released from minerals, (5) characteristics of clays, perchlorates, sulfates, and hydrated minerals from evolved gas analysis (EGA), and (6) identification of organic compounds extracted from soils and rocks. From 2013 to the present the Mars Atmosphere and Volatile Evolution (MAVEN) mission has been measuring the upper atmosphere of Mars to study its physics and chemistry and the response to solar drivers. The Neutral Gas and Ion Mass Spectrometer measurements of atmospheric structure and its variability and of primordial argon isotopes help constrain models of loss to space that have profound consequences for major climate transitions from the early wet environment to the present state.

About the Speaker:

Paul Mahaffy has participated for many years at Goddard Space Flight Center in study of planetary atmospheres and surface environments and in development of space qualified instrumentation. After serving for 10 years as Chief of the Planetary Environments Laboratory, he was privileged to serve for 5 years as the Director of the Solar System Exploration Division at NASA Goddard which conducts theoretical and experimental research to explore the solar system and understand the formation and evolution of planetary systems. Laboratories within the Division investigate areas as diverse as astrochemistry, planetary atmospheres, geochemistry, geophysics, geodynamics, space geodesy, extrasolar planetary systems, and comparative planetary studies. Scientists within the Division participate in planetary missions such as LRO, MSL, MAVEN, MESSENGER, JUNO, Cassini, OSIRIS-REx, MOMA, and Lucy and are active in formulating mission and investigation concepts.

Paul Mahaffy's own research interests include: chemical and isotopic composition of planetary atmospheres and surfaces, astrobiology, and advanced instrument development for organic and light isotope analysis in planetary targets.

Paul Mahaffy served as the Principal Investigator (PI) on the Sample Analysis at Mars Instrument Suite on the Curiosity Rover currently operating on the surface of Mars to explore its past and present habitability. He was also PI on the Neutral Gas and Ion Mass Spectrometer on the MAVEN mission orbiting Mars to better understand how its atmosphere was lost and the PI on the Neutral Mass Spectrometer on the LADEE mission that recently concluded a successful mission in lunar orbit exploring the tenuous lunar exosphere. One of his past career highlights was studying the atmosphere of Jupiter to test giant gas planet formation models using data from a mass spectrometer on the Galileo Probe as it parachuted deep into that atmosphere.