Discoverer Mariner 9 | ||
 | ||
Peak 13.9 kilometres (46,000 ft) above plains
16 kilometres (52,000 ft) above datum | ||
Elysium Mons is a volcano on Mars located in the volcanic province Elysium, at 25.02°N 147.21°E / 25.02; 147.21, in the Martian eastern hemisphere. It stands about 13.9 km (46,000 ft) above the surrounding lava plains, and about 16 km (52,000 ft) above the Martian datum. Its diameter is about 240 km (150 mi), with a summit caldera about 14 km (8.7 mi) across. It is flanked by the smaller volcanoes Hecates Tholus to the northeast, and Albor Tholus to the southeast.
Elysium Mons was discovered in 1972 in images returned by the Mariner 9 orbiter.
The terrestrial volcano Emi Koussi (in Chad) has been studied as an analog of Elysium Mons. The two shield volcanoes have summit calderas of similar size, but Elysium Mons is 3.5 times larger in diameter and 6 times higher than its counterpart on Earth.