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Selected Works of Edwin J. Mierkiewicz
Presentation
MAVEN/IUVS Perispse Lyman-Alpha Observations: Variability and Constraints on H and CO2 Abundance
American Geophysical Union Fall Meeting (2017)
  • Andrea C. G. Hughes, Embry-Riddle Aeronautical University
  • Michael Chaffin, Laboratory for Atmospheric and Space Physics
  • Edwin J. Mierkiewicz, Embry-Riddle Aeronautical University
  • Jean-Yves Chaufray, LATMOS, Laboratoire Atmospheres, Milieux, Observations Spatiales
  • Justin Deighan, Laboratory for Atmospheric and Space Physics
  • Nick M. Schneider, Laboratory for Atmospheric and Space Physics
  • Edward Thiemann, Laboratory for Atmospheric and Space Physics
  • John T. Clarke, Boston University
  • Majd Mayyasi, Boston University
  • Sonal K. Jain, Laboratory for Atmospheric and Space Physics
  • Matteo Michael James Crismani, Laboratory for Atmospheric and Space Physics
  • Arnaud Stiepen, Laboratory for Atmospheric and Space Physics
  • Franck Montmessin, LATMOS, Laboratorie Atmospheres, Milieux, Observations Spatiales
  • Francis Epavier, Laboratory for Atmospheric and Space Physics
  • Ian F. Stewart, Laboratory for Atmospheric and Space Physics
  • Bill McClintock, Laboratory for Atmospheric and Space Physics
  • Greg Holsclaw, Laboratory for Atmospheric and Space Physics
  • Bruce Martin Jakosky, Laboratory for Atmospheric and Space Physics
Abstract
The abundance of spectroscopic and geomorphologic evidence demonstrating that liquid water
once flowed on Mars raises significant questions regarding the history of Martian water and the
evolution of the atmosphere into the current hyper-arid climate. Using data from the Imaging
UltraViolet Spectrograph (IUVS) onboard the Mars Atmosphere and Volatile EvolutioN (MAVEN)
spacecraft, we evaluate the hydrogen Lyman-alpha emission (121.6 nm) across multiple Martian
years and solar zenith angles. We create altitude-intensity profiles of atmospheric hydrogen
emission using periapse data from all MAVEN orbits to-date. Due to the optically thin emission of
the UV-doublet scale height of mid-ultraviolet IUVS data, we are able to indirectly probe the
temperature of the atmosphere. By combining mid-ultraviolet and far-ultraviolet IUVS data, we
extract temperatures and densities of the upper atmosphere and fit the data using a radiative
transfer forward model. Below 120 km, the H Lyman-alpha emission is absorbed by CO2,
providing constraint on CO2 in the lower thermosphere. Fitting the altitude-intensity curves below
120 km altitude and comparing spatial and temporal variations of the profiles allows us to
constrain CO2 abundances. The results of this work, in combination with other MAVEN findings,
will provide better constraints on Martian H and CO2 densities and determining neutral
temperatures, as well as a more thorough understanding of the evolution of the Martian
atmosphere through time.

Keywords
  • Mars,
  • atmosphere,
  • hydrogen emission
Disciplines
Publication Date
December 14, 2017
Location
New Orleans, LA
Comments
Abstract #P43E-2936.
Citation Information
Andrea C. G. Hughes, Michael Chaffin, Edwin J. Mierkiewicz, Jean-Yves Chaufray, et al.. "MAVEN/IUVS Perispse Lyman-Alpha Observations: Variability and Constraints on H and CO2 Abundance" American Geophysical Union Fall Meeting (2017)
Available at: http://works.bepress.com/edwin_mierkiewicz/91/