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arXiv · 2607.07009

Impact of May 2024 ICME Event on Martian UV Dayglow Emissions using MAVEN/IUVS and EMM/EMUS Observations

Aadarsh Raj Sharma·Vaghamshi Dhruv Dhaneshbhai·Lot Ram·Sumanta Sarkhel
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Abstract

We present first near-simultaneous observations of large-scale spatial response of the Martian H Lyman-α and atomic oxygen dayglow emissions (O(3S) 130.4 nm and O(5S) 135.6 nm) during May 2024 interplanetary coronal mass ejection (ICME). Using coordinated near-simultaneous observations from MAVEN/Imaging Ultraviolet Spectrograph (IUVS) and the EMM/Emirates Mars Ultraviolet Spectrometer (EMUS), we have identified pronounced enhancements in all three emissions relative to quiet-time conditions. Interestingly, coordinated IUVS limb and EMUS disk observations reveal that ICME-driven response extends vertically through the thermosphere and horizontally across broad ranges of latitude, longitude, local-time, and solar zenith angle. Concurrent enhancement of hydrogen and oxygen emissions indicates the simultaneous contribution of proton and electron-driven excitation mechanisms during ICME. These findings reveal a novel planetary-scale response of the Martian dayglow. By highlighting the critical role of energetic-particle precipitation in amplifying this global response, our work carries crucial implications for understanding Martian thermospheric response during intense solar transients.

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Aadarsh Raj Sharma, Vaghamshi Dhruv Dhaneshbhai, Lot Ram, Sumanta Sarkhel. 2026-07-08. Impact of May 2024 ICME Event on Martian UV Dayglow Emissions using MAVEN/IUVS and EMM/EMUS Observations. https://arxiv.org/abs/2607.07009

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