Facts About Mars’s Volcanoes
Published September 27, 2026 · FactsSeeker
Mars is a cold, dusty desert planet with a surface shaped by several geologic and atmospheric processes. NASA’s fact sheet identifies extinct volcanoes as part of that landscape and highlights Olympus Mons as the main named example. These facts focus only on what the supplied NASA source supports: what the volcanoes are called, how Olympus Mons is described, and what Martian surface conditions help frame those volcanic features.
Mars’s volcanoes are identified as extinct
NASA’s Mars fact sheet places volcanoes among the planet’s defining features and identifies them as extinct. For this topic, that matters because the available source supports a history of volcanism on Mars, not observed present-day eruptions. [1]
Volcanism is one force that reshaped the Martian landscape
NASA groups volcanoes with impact craters, crustal movement, and atmospheric conditions as agents that changed Mars over many years. That puts volcanic features in the same broad landscape-building category as impacts and crustal changes when describing how the planet’s surface became so varied. [1]
Olympus Mons is the named volcano highlighted by NASA
The fact sheet singles out Olympus Mons when discussing Martian volcanoes. Because the page identifies it by name and gives measurements for it, Olympus Mons is the main volcano that can be described in detail from this source. [1]
Olympus Mons is described as the largest volcano in the solar system
NASA states that Olympus Mons is the largest volcano in the solar system. This is a comparative statement about volcanoes, not simply about mountains, and it is the strongest ranking the source provides for Martian volcanism. [1]
Olympus Mons rises more than 25 miles from base to summit
NASA gives Olympus Mons a height of more than 25 miles from base to summit. That wording describes relief across the volcanic edifice itself, rather than elevation above an Earth-style sea level reference. [1]
NASA also expresses that height in feet and kilometers
The same height is given as more than 132,000 feet, or 40 kilometers. Keeping the source’s units is important because the fact sheet presents them as parallel ways to state the volcano’s scale. [1]
Its base is compared with Arizona
NASA says the base of Olympus Mons covers an area as large as the state of Arizona. The comparison emphasizes that the volcano is not only tall; it also spreads across a very broad footprint. [1]
NASA compares Olympus Mons with Mount Everest
NASA uses Mount Everest as an Earth comparison and says Olympus Mons dwarfs it. The source gives Everest’s height as 29,029 feet, or 8,848 meters, which helps show why the comparison is meant to convey exceptional scale. [1]
Mars’s volcanic features sit on a rocky terrestrial planet
NASA describes Mars, like the other terrestrial planets, as having a central core, a rocky mantle, and a solid crust. That geology matters for volcanoes because the volcanic landscapes discussed by the source are part of a solid rocky world. [1]
The Martian crust has measured thickness ranges
NASA says the Martian crust is between 6 and 30 miles deep, also stated as 10 to 50 kilometers. Those crust values provide context for the rigid outer layer that holds Mars’s surface features, including its volcanoes. [1]
The mantle lies below the crust
Below the crust, NASA describes a rocky mantle between 770 and 1,170 miles thick, or 1,240 to 1,880 kilometers. This matters because volcanoes are surface features tied to a planet’s deeper rocky structure, even though the fact sheet does not trace specific magma pathways. [1]
Mars is smaller than Earth but has a large exposed surface
NASA says Mars is about half the diameter of Earth, yet its surface has nearly the same area as Earth’s dry land. That context makes the scale of Martian volcanic landscapes easier to appreciate without inventing additional measurements. [1]
The volcanic landscape is part of a dusty desert world
NASA introduces Mars as a dusty, cold, desert world with a very thin atmosphere. Any discussion of its volcanoes has to place them within that dry surface environment rather than within Earth-like weather or vegetation. [1]
Mars’s colors come from oxidized iron and dust
At the surface, NASA says Mars shows colors such as brown, gold, and tan. Its famous red appearance comes from oxidized iron in rocks, regolith, and dust, so views of Martian volcanic landforms belong within that wider surface-color setting. [1]
Dust storms can affect how the surface is seen
NASA says winds on Mars can sometimes raise dust storms that cover much of the planet. After such storms, dust can take months to settle, which is relevant when thinking about how exposed volcanic landforms may be obscured or coated. [1]
Sources & further reading
NASA’s fact sheet identifies Martian volcanoes as extinct and gives headline measurements for Olympus Mons. It does not date individual eruptions or list every volcanic province, so this page stays within that scope.
Sources checked 2026-09-27. Our approach to facts · Suggest a correction