Study Links Mars Crust Split to Southern Mantle 200-400°C Hotter
Updated
Updated · Scientific American · Aug 26
Study Links Mars Crust Split to Southern Mantle 200-400°C Hotter
3 articles · Updated · Scientific American · Aug 26
Summary
A Nature study found Mars’s southern mantle is 200 to 400°C hotter than the north, tying the temperature gap directly to the planet’s 25-km crustal thickness divide.
Using 16 years of radio tracking from three orbiters, researchers applied tidal tomography to measure how Mars flexes over its 687-day year and inferred a mantle stiffness contrast of more than 20%.
Their models showed the boundary between softer southern rock and stiffer northern rock tracks the surface dichotomy itself, strengthening the case that Mars’s biggest visible split extends deep into the planet.
The result could revive hybrid origin theories—an ancient impact plus ongoing heat retention or convection—though outside scientists said the observations are stronger than the thermal interpretation and noted unresolved puzzles such as Tharsis volcanism.
Berne said the next step is direct temperature measurements at multiple landing sites, while the orbit-only method could also probe interiors of harder-to-reach worlds such as Mercury, Enceladus and Pluto.