Studies on Mars have revealed hidden structures and dense areas beneath old ocean beds, influencing the volcanic activity of Olympus Mons. Using gravity data and new insights from NASA’s InSight mission,

To uncover the hidden features, researchers employed a sophisticated technique that measures minute changes in the orbits of satellites around Mars. The tiny deviations result from variations in the planet’s gravity field, which are influenced by the distribution of mass beneath the surface, Study Finds reports.

The research team uncovered a vast, lightweight structure approximately 1,750 kilometres wide and located 1,100 kilometres beneath the surface, forcing the Tharsis region to expand upward.

A new study of Mars' gravitational field has revealed mysterious structures hiding beneath the sediment layers of a lost ocean. Experts still aren't sure what they are or how they formed.