Mars Gravity Map.

A new map of Mars' gravity made with three NASA spacecraft is the most detailed to date, providing a revealing glimpse into the hidden interior of the Red Planet. Satellites always orbit a planet’s center of mass, but can be pulled slightly off course by the gravity of massive features like Olympus Mons, the solar system’s tallest mountain. Now, scientists at Goddard Space Flight Center have used these slight orbital fluctuations to map the gravity field of Mars, providing fresh insights into its crustal thickness, deep interior, and seasonal variations of dry ice at the poles. The new gravity map will also help to put future spacecraft into orbit more precisely, ensuring that the Mars fleet continues to return a massive trove of data.