Observations and Impacts of the 10 September 2017 Solar Events at Mars: An Overview and Synthesis of the Initial Results

Abstract

On 10 September 2017, some of the strongest solar activity occurred in association with active region 12673 (AR2673), including an X-class solar flare and a fast coronal mass ejection. Although AR2673 was not centrally facing Mars, the activity impacted the local space weather conditions at Mars. We give an overview of observations obtained from the Mars Atmosphere and Volatile EvolutioN, Mars Science Laboratory, and Mars Express missions. Numerical results from the Wang-Sheeley-Arge (WSA)-Enlil-cone model together with Earth/L1 and STEREO-A observations are also presented to provide some heliospheric context. We discuss the initial results on the space weather impacts at Mars, which include heating of the upper atmosphere by solar flare emissions, flare-related enhancements of ion and neutral densities, solar energetic particles impacting the atmosphere and surface, bright emissions of a diffuse (global) aurora, deeply penetrating interplanetary magnetic fields over the Martian dayside, and enhanced atmospheric escape rates.