Welcome to Scratching the Surface with Caitlin Ahrens, the Pluto Manager at the Center for Space and Planetary Science.
Just below Mars' equator lies the Tharsis Bulge, a series of volcanic mountains including Olympus Mons, which is two and a half times the height of Mount Everest. The region is thought to be a product of a giant hot spot. Because Mars lacks tectonic plates, the lava pooled in this region to create a bulging effect.
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