P21A-2060
MAVEN/IUVS Apoapse Observations of the Martian FUV Dayglow
Tuesday, 15 December 2015
Poster Hall (Moscone South)
John Correira1, Joseph Scott Evans2, Michael H Stevens3, Nicholas McCord Schneider4, Ian F Stewart5, Justin Deighan5, Sonal Jain5, Michael Chaffin5, Matteo Michael James Crismani5, Bill McClintock5, Greg Holsclaw5, Franck Lefèvre6, Daniel Lo7, John T Clarke8, Stephen W Bougher9, Jared Micheal Bell10, Paul R Mahaffy11, Bruce Martin Jakosky5 and Arnaud Stiepen4, (1)Computational Physics Inc. Springfield, Springfield, VA, United States, (2)Computational Physics Inc, Springfield, VA, United States, (3)US Naval Research Laboratory, Washington, DC, United States, (4)University of Colorado at Boulder, Boulder, CO, United States, (5)Laboratory for Atmospheric and Space Physics, Boulder, CO, United States, (6)LATMOS Laboratoire Atmosphères, Milieux, Observations Spatiales, Paris Cedex 05, France, (7)University of Arizona, Tucson, AZ, United States, (8)Boston University, Boston, MA, United States, (9)University of Michigan Ann Arbor, Ann Arbor, MI, United States, (10)National Institute of Aerospace, Yorktown, VA, United States, (11)NASA Goddard Space Flight Center, Greenbelt, MD, United States
Abstract:
We present FUV data (115 - 190 nm) from MAVEN/IUVS apoapse mode observations for the Oct 2014 through Feb 2015 time period. During apoapse mode the highly elliptical orbit of MAVEN allows for up to four apoapse disk images by IUVS per day. Maps of FUV feature intensities and intensity ratios as well as derived CO/CO2 and O/CO2 column density ratios will be shown. Column density ratios are derived from lookup tables created using the Atmospheric Ultraviolet Radiance Integrated Code [Strickland et al., 1999] in conjunction with observed intensity ratios. Column density ratios provide a measure of composition changes in the Martian atmosphere. Due to MAVEN's orbital geometry the observations from this time period focus on the southern hemisphere. The broad view provided by apoapse observations allows for the investigation of spatial and temporal variations (both long term and local time) of the atmospheric composition (via the column density ratios). IUVS FUV intensities and derived column density ratios will also be compared with model results from Mars Global Ionosphere/Thermosphere Model (MGITM) and the Mars Climate Database (MCD).
