Neutral density response to solar flares at Mars. Issue 21 (11th November 2015)

• Record Type: Journal Article
• Authors: Thiemann, E. M. B.; Eparvier, F. G.; Andersson, L. A.; Fowler, C. M.; Peterson, W. K.; Mahaffy, P. R.; England, S. L.; Larson, D. E.; Lo, D. Y.; Schneider, N. M.; Deighan, J. I.; McClintock, W. E.; Jakosky, B. M.
• Is Part Of: Geophysical research letters. Volume 42:Issue 21(2015:Nov.)
• Page Start: 8986
• Page End: 8992
• Publication Date: 2015-11-11
• Subjects: Mars -- thermosphere -- neutral density -- solar flare -- flare; Geophysics -- Periodicals; Planets -- Periodicals; Lunar geology -- Periodicals; 550
• DOI: 10.1002/2015GL066334
• Languages: English
• ISSNs: 0094-8276

Abstract

Abstract: First direct observations of heating of the Mars neutral atmosphere by solar flares are presented in this study. Solar flares were detected using the Extreme Ultraviolet Monitor on board the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft, and upper atmospheric temperature enhancements were determined by changes in the density scale height of Argon (Ar) made by the Neutral Gas and Ion Mass Spectrometer also on board MAVEN. We analyzed 14 M‐class or greater flares that occurred during the early part of the MAVEN mission in addition to a 30 day period of high flare activity during May 2015. We report that the Mars dayside upper atmosphere shows significant heating near the flare soft X‐ray peak; and it responds and recovers rapidly to heating from M‐class or larger flares. In addition, we present atmospheric density versus altitude profiles that were taken near the soft X‐ray peak of two flares. Key Points: First observations of neutral heating at Mars due to solar flares are reported The upper atmosphere shows significant heating near the flare soft X‐ray peak The Mars atmosphere responds and recovers rapidly to heating from M‐class flares