Tidal gravity data point to hot spot beneath Mars' crustal divide
Scientists modeled how Mars' gravity field shifts over time due to solar tides, using a technique that lets gravity harmonic coefficients vary periodically at annual, semi-annual and other frequencies within orbit-determination software. By tracking these small periodic gravity variations, they detected a thermal anomaly located beneath the boundary separating Mars' northern lowlands and southern highlands, known as the crustal dichotomy.