Scientists discover vast underground thermal anomaly on Mars

Discovery of a Martian Thermal Anomaly

A study published in Nature reports the discovery of a significant thermal anomaly deep within Mars. Researchers found that the planet's mantle, the layer between the crust and core, is substantially hotter in the southern hemisphere compared to the northern half, by 400 to 750°F.

Addressing the Martian Dichotomy

This temperature difference could help explain the long-standing mystery of the "Martian dichotomy," which refers to the distinct geographical differences between Mars' hemispheres. The northern hemisphere consists of lowlands, potentially once home to an ocean, while the southern hemisphere is characterized by higher elevation highlands. The new data suggests the crustal dichotomy reflects a similarly divided interior.

Methodology: Tidal Tomography

To make this discovery, scientists employed a novel technique called tidal tomography. This involved analyzing 16 years of tracking data from three NASA orbiters: Mars Global Surveyor, Mars Odyssey, and Mars Reconnaissance Orbiter. These data measured slight gravitational wobbles of Mars during its orbit around the Sun, allowing researchers to infer internal temperatures.

Implications for Martian Science

While the study does not definitively answer the origin of the dichotomy, it provides new evidence for internal processes in the mantle, such as convection, or insulation under the highlands. This research adds to the understanding of Mars' geological evolution and its potential to have hosted life.