Of Venus, Earth, and Mars, only Earth possesses a global dynamo magnetic field, and it has been widely assumed for decades that this magnetic field has contributed to Earth's present surface habitability by preventing the atmosphere from being stripped away to space over time. This assumption has been called into question in recent years based on both theoretical arguments and observations returned by spacecraft. This presentation will summarize the arguments "for"and "against" the idea that magnetic fields are essential for surface habitability. Three ongoing parallel efforts to address this question will be presented: (1) analysis of spacecraft observations of the escaping Martian atmosphere; (2) computer simulations of atmospheric escape from magnetized Mars-like planets; and (3) a recently selected NASA Heliophysics team science effort. Finally, the presentation will discuss the implications of these efforts for our search for habitable worlds elsewhere in our galaxy, and for climate histories in our own solar system.

About the Speaker:

Dave Brain is an Associate Professor of Astrophysical and Planetary Sciences at the University of Colorado Boulder. Dave received his Bachelor's degree from Rice University and his Ph.D. from the University of Colorado before spending 8 years at UC Berkeley as a postdoc and Research Scientist. Dave's research centers around the evolution of planetary atmospheres and planetary plasma environments. He is the Deputy PI of NASA's MAVEN mission currently orbiting Mars and the Project Scientist for the Emirates Mars Mission scheduled to launch in July of this year.
                   
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