If you thought that Mt. Everest was the highest peak known to humankind, then guess again. Since further exploration of Mars, NASA has claimed that Olympus Mons, a volcano located in the Tharsis Montes region of the planet, would currently hold that title. As the volcano spans 374 miles in diameter (which is approximately the size of Arizona State), and 16 miles high, it’s also topped with a caldera that is 50 miles wide that is located at the summit.
The largest volcano on Earth which is Mauna Loa located in the Hawaiian Islands reigns 6.3 miles high, and 75 miles in diameter. This makes the volume of Olympus Mons roughly 100 times larger than that of Mauna Loa. The volcanoes in the Tharsis region on Mars typically run 10-100 times larger than the counterparts of our home planet.
The Martian crust moves differently than that of Earth, which is another reason why the volcanoes differ so much in size. On Earth, the crustal plates continually move above stationary hotspots beneath them. An example are the Hawaiian Islands, which are the result of the Pacific plate’s northwestern movement over a stagnant hotspot below that consistently produces lava. On Earth, existing volcanoes become inanimate while newly formed structures commence as the plate moves over the hotspot. It’s this action that distributes the volume of lava to multiple volcanoes, as opposed to one large volcano. The action is quite the opposite on Mars as it’s the crust that remains stationary with the hotspot, that as a result produces one extremely large volcano.