Mars southern interior is 200-400C hotter than other regions, study says
- Mars maintains a deep interior temperature anomaly in its southern highlands that is 200 to 400 degrees Celsius hotter than other regions, according to an investigation published in...
- Scientists analyzed how the planet responds to tidal forces generated by its orbit around the Sun.
- The high-temperature zone lines up directly beneath the rugged, heavily cratered terrain of the southern hemisphere.
Mars maintains a deep interior temperature anomaly in its southern highlands that is 200 to 400 degrees Celsius hotter than other regions, according to an investigation published in Nature. The finding does not mean the surface of Mars is losing its freezing environment. The thermal anomaly sits deep inside the Martian mantle, far below the reach of active landers and rovers operating on the surface, and it does not imply an increase in the temperatures experienced by probes or future explorers on the ground.
Tidal Tomography Reveals Mantle Asymmetry
Scientists analyzed how the planet responds to tidal forces generated by its orbit around the Sun. The research team applied a technique called tidal tomography to study the interior structure indirectly through variations in the gravitational field.
The analysis revealed variations of up to 300 percent compared to what researchers would expect from a completely symmetrical planet. These differences point to a mantle beneath the southern highlands that retains significantly more heat than the northern interior.
Southern Mantle Temperatures Match Martian Crustal Dichotomy
The high-temperature zone lines up directly beneath the rugged, heavily cratered terrain of the southern hemisphere. This geographic distribution matches the well-known crustal dichotomy of Mars, which separates the high southern lands from the low northern plains. According to the study, the southern mantle can register a temperature 200 to 400 degrees Celsius higher than other areas of the Martian interior, and this thermal difference fits with that major peculiarity of the crust. The research links both characteristics through the physical properties of the mantle.
One hypothesis suggests that regional mantle convection transports deep heat upward, while another proposes that a thicker southern crust acts as a thermal blanket that traps heat over billions of years.
Future Electromagnetic Measurements
The elevated temperatures in the mantle could drive localized melting and help explain the thermal and magnetic history of Mars. The study notes that upcoming electromagnetic measurements could determine whether pockets of partially molten material exist in the mantle.