Martian Thermospheric Response to an X8.2 Solar Flare on 10 September 2017 as Seen by MAVEN/IUVS

Sonal K. Jain (1) , Justin Deighan (1) , N. M. Schneider (1) , A. I. F. Stewart (1) , J. S. Evans (1) , E. M. B. Thiemann (1) , M. S. Chaffin (1) , M. Crismani (1) , M. H. Stevens (2) , M. K. Elrod (3) , Arnaud Stiepen (4) , W. E. Mcclintock (1) , D. Y. Lo (5) , J. T. Clarke (6) , F. G. Eparvier (1) , Franck Lefèvre (7) , Franck Montmessin (7) , G. M. Holsclaw (1) , P. C. Chamberlin (1) , B. M. Jakosky (1)

1 LASP - Laboratory for Atmospheric and Space Physics [Boulder]
2 NRL - Naval Research Laboratory
3 GSFC - NASA Goddard Space Flight Center
4 LPAP - Laboratoire de Physique Atmosphérique et Planétaire
5 LPL - Lunar and Planetary Laboratory [Tucson]
6 CSP - Center for Space Physics [Boston]
7 PLANETO - LATMOS

We report the response of the Martian upper atmosphere to a strong X‐class flare on September 10, 2017 as observed by the Imaging Ultraviolet Spectrograph (IUVS) instrument aboard the Mars Atmosphere Volatile EvolutioN (MAVEN) mission. The solar flare peaked at 16:24 hrs UT and IUVS dayglow observations were taken about an hour after the flare peak. Retrieved temperatures from IUVS dayglow observations show a significant increase during the flare orbit, with a mean value of ∼270 K and a maximum value of ∼310 K. The retrieved temperatures during the flare orbit also show a strong latitudinal gradient, indicating that the flare induced heating is limited between low‐ and mid‐latitudes. During this event IUVS observed an ∼70% increase in the observed brightness of CO₂⁺ Ultraviolet Doublet and CO Cameron band emission at 90 km, where high‐energy photons (< 10 nm) deposit most of their energy.

Domaines: Astrophysique [astro-ph]

Sonal K. Jain, Justin Deighan, N. M. Schneider, A. I. F. Stewart, J. S. Evans, et al.. Martian Thermospheric Response to an X8.2 Solar Flare on 10 September 2017 as Seen by MAVEN/IUVS. Geophysical Research Letters, 2018, 45 (15), pp.7312-7319. ⟨10.1029/2018GL077731⟩. ⟨insu-01798721⟩