Stephen W Bougher

Andrew F. Nagy Collegiate Research Professor

Education:

Ph.D., Planetary Aeronomy, University of Michigan (1984)
M.S., Astro-geophysics, University of Colorado (1980)
B.A., Physics, Northwestern University (1977)

Research:

Comparative Planetary Upper Atmospheres

Doctoral Students:

Amanda Brecht
Tamara McDunn

Specializations and Research Interests

The comparative approach to planetary problems is becoming increasingly fruitful as new information from various planet atmospheres is assimilated. The long-term objective in my program of research is to contrast and compare the processes responsible for the structure and dynamics of the Venus, Earth, Mars and Jovian planet upper atmospheres. This is important to our overall understanding of how atmospheres are driven and how they change over time, both naturally and in the case of Earth as a result of human influence. My study of upper atmospheres specifically involves a systematic examination of their neutral/ion chemistry, radiation, airglow, and dynamics above ~50 km. This strategy includes modeling their mesospheric, thermospheric, and ionospheric responses to different forcings using the 3-D thermospheric general circulation model (TGCM) utility at the National Center for Atmospheric Research (NCAR). The TGCM couples chemical, radiative, and dynamical processes self- consistently; this feedback is critical to understanding upper atmosphere responses to changing external forcings (solar, magnetospheric, tidal, gravity wave). Data from various terrestrial and planetary spacecraft missions and ground-based observations is being used to validate these models and compare the relevant atmospheric processes. Presently, aerobraking data from three Mars orbiters (Mars Global Surveyor, Mars Odyssey and Mars Reconnaissance Orbiter) is being used to constrain Mars TGCM simulations, from which the underlying dynamical processes linking the Mars lower and upper atmospheres can be investigated. In addition, a Jupiter TGCM is being exercised to explore and dynamical, thermal, and compositional responses to auroral/magnetospheric forcing in the Jovian upper atmosphere. A web site is available that presents an archive of Venus, Earth, and Mars upper atmosphere TGCM simulations.

Research Projects

• Comparing the energetics and dynamics of the upper atmospheres of Venus, Earth, Mars, and Jupiter using the TGCM utility
• Aerobraking in the lower thermosphere of Mars (Mars Global Surveyor, 2001 Mars Odyssey, Mars Reconnaissance Orbiter)
• Gravity wave/tidal coupling of the lower and upper atmospheres of Mars
• Mars ionospheric structure and its implications for the neutral atmosphere (below) and the solar wind interaction (above)
• Jupiter's auroral energetics and implications for its global dynamics and structure
• Magnetosphere-ionosphere coupling at Jupiter
• Titan thermospheric dynamics driven by solar EUV and Saturn magnetospheric forcing
• Analysis of INMS data from the Cassini Mission using the Titan GITM code

Honors, Awards and Accomplishments

• OVPR Outstanding Research Achievement Award, U. of Michigan: 2004
• College of Engineering Outstanding Research Scientist Award, U. of Michigan: 2007
• National Academy of Sciences COMPLEX Committee Member: 2002 - 2006
• Mars Exploration Program MEPAG Goals Committee Member: 2002 - 2007
• Associate Editor, Journal of Geophysical Research — Space Physics: 2002 - 2006
• National Center for Atmospheric Research Affiliate Scientist: 2003 - 2011
• OVPR Andrew F. Nagy Collegiate Research Professorship: 2009 - 2014

Professional Service

• Mars Global Surveyor Mission (1995-1999), Aerobraking team
• Nozomi/JAPAN (1995-2005). CO-I on the Neutral Mass Spectrometer (NMS) focusing upon the study of the Mars neutral-ion upper atmosphere
• 2001 Mars Odyssey Orbiter (2001-2002), Aerobraking Team
• 2005 Mars Reconnaissance Orbiter (2002-2009), Accelerometer Facility Team Member
• Venus Express Participating Scientist data analysis (2006-2010) SPICAV Instrument

Publications

See research webpage.