Scientists have discovered large-scale structures on Mars that could be volcanic in origin or material compressed by impact with meteorites. These structures were discovered in the northern polar plains, which are covered by a thick layer of sedimentary rock believed to have accumulated on an ancient sea floor.

Researchers measured Mars’ gravitational field by examining the planet’s interior and found that the north polar regions are about 300-400 kg/m3 denser than their surroundings.

The discovery was made through an analysis combining models and data from several missions, including NASA’s InSight mission.

Dr. Bart Ruth from Delft University of Technology (TU Delft) said: “We discovered around 20 objects of various sizes scattered around the region surrounding the Arctic cap. There are apparently no traces of them on the surface. However, thanks to gravitational field measurements, we now have an exciting insight into the earlier history of the northern hemisphere of Mars.”

Researchers have discovered new information about the structures underlying the vast Tharsis Rise volcanic region, which includes the massive volcano Olympus Mons. Despite its high density of volcanoes, the Tharsis region is much higher than the average surface of Mars and is surrounded by a region of relatively weak gravity. This could be explained by a large lava plume moving toward the surface from deep within the Martian interior.

NASA’s InSight mission has provided new information about the solid outer layer of Mars, which requires rethinking the morphology of the Olympus Mons volcano and its surroundings. “This suggests that there may still be activity inside Mars affecting the surface and possibly creating new volcanic formations,” Dr Root said.

Dr. Ruth is part of the team proposing the Mars Quantum Gravity (MaQuls) mission, which aims to map the gravitational field of Mars in detail. This mission will allow us to better study the planet’s interior and understand ongoing convection in the mantle, as well as dynamic surface processes such as seasonal changes in the atmosphere and the detection of subsurface reservoirs.

“Observations with MaQuIs will allow us to better probe the interior of Mars. This will help us learn more about these mysterious hidden features as well as understand dynamic surface processes,” said Dr Lisa Werner from DLR, who presented the MaQuIs mission at the European Science Congress (EPSC) in Berlin.