Overview
- NASA disclosed in May 2026 that MAVEN data reveal the Zwan-Wolf effect inside Mars’ ionosphere during a strong solar storm in December 2023.
- The peer-reviewed study in Nature Communications reports large magnetic structures plunging below 200 km, with five features tracked down to about 185 km and local plasma density dropping 30–40%.
- Lead author Christopher Fowler first flagged odd magnetic “wiggles,” then a multi-instrument review of charged particles and fields ruled out other causes and matched the Zwan-Wolf mechanism.
- The effect squeezes and redistributes ionospheric plasma, pointing to a pathway for atmospheric loss on Mars and likely operating, often too weak to see, on unmagnetized worlds like Venus and Titan.
- MAVEN has been out of contact since December 6, 2025, and NASA formed an anomaly review board in February 2026 to assess the spacecraft’s state and prospects for recovery.