Overview
- The study, published Aug. 27, 2026, applied a tidal-tomography technique to decades of gravity-tracking data from Mars Global Surveyor, Mars Odyssey and Mars Reconnaissance Orbiter to map Mars’s deep interior.
- Researchers report the mantle beneath Mars’s southern hemisphere is roughly 200–400 °C warmer than the northern mantle and may be partially molten.
- A hotter southern mantle helps explain prior puzzles such as strong magnetic signatures in southern rocks and faster seismic wave attenuation recorded by NASA’s InSight lander.
- Authors say the cause is still unknown and present three testable hypotheses — an ancient giant impact, long-lived mantle convection, or thick southern crust trapping heat — that require higher-resolution gravity, seismic or geophysical data to resolve.
- The tidal-tomography method, developed by lead author Alexander Berne and funded by NASA, can be applied to other bodies and will help design future missions that target Mars’s interior structure.