Martian ionospheric response during the may 2024 solar superstorm

Journal article

Solar energetic events can have considerable effects on planetary ionospheres. However, the erratic nature of these solar energetic events make observations difficult. Here we show a mutual radio occultation observation, which serendipitously occurred just 10 minutes after a large solar flare impacted Mars. This resulted in the largest lower ionospheric layer ever recorded, where it was 278% its typical size. We used in-situ soft x-ray irradiance measurements to show a threefold increase in flux. This infers a different relation of soft X-ray to this layer's density than previously thought, with variations depending on the amount of spectrum 'hardening' leading to the increase of ionisation from secondaries.

Authors: Parrott, J; Sánchez-Cano, B; Svedhem, H; Witasse, O; Meggi, D

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Nature Research
• Journal: Nature Communications
• Volume: 17
• Issue: 1
• Pages: 2017
• Publication date: 2026-03-05
• DOI: 10.1038/s41467-026-69468-z
• EISSN: 2041-1723
• ISSN: 2041-1723
• Language: English
• Keywords: Radio occultation; Martian; Solar flare; Atmosphere of Mars; Ionosphere; Occultation; Mars Exploration Program; Flare; Irradiance