The Largest Mountain in the Solar System

by | Apr 12, 2018


Olympus Mons

Which mountain is the largest in the Solar System? It’s not Mount Everest at a “mere” 29,029 feet. Nor is it Mauna Kea which is “only” about 13,000 feet above sea level, but has a total rise from the surface of the earth of 33,500 feet.

The highest mountain in the solar system is Olympus Mons and is an absolute monster of a mountain, rising 16.7 miles (88,580 feet) above the mean surface height of Mars.  That is about three times the height of Mt. Everest.  It is approximately 350 miles in width at its base (meaning that it is 20 times as wide as it is tall) – making it about the size of the state of Arizona. The base of the mountain is surrounded by a cliff that is 3 miles tall.   The mountain has a very shallow slope – about 5 degrees. That means that a person standing on the surface of Mars would be unable to view the upper profile of the volcano even from a distance as the curvature of the planet and the volcano itself would obscure it.


The outline of Arizona overlaid on Olympus Mons

Olympus Mons is a shield volcano, formed by layers of stacked, slow flowing magma.

How is Olympus Mons so big?  A number of reasons explain its size. First, Mars has less gravity and with less gravitational pull, the volcanoes can grow higher without collapsing under their own weight. Second, the crust on Mars doesn’t move the way it does on Earth – Mars has very limited tectonic plate movement. On Earth, the hot spots that end up forming volcanoes remain stationary but Earth’s plates move above them. Thus, as tectonic plates move over volcanic hot spots, new volcanoes are formed and the existing ones become extinct. This distributes the total volume of lava among many volcanoes rather than one large volcano. On Mars, the crust remains stationary and the lava piles up in one, very large volcano. Third, Mars had high eruption rates that generated a lot of lava which formed Olympus Mons.

A related note: the Pixies have an outstanding song called “Bird Dream of the Olympus Mons” off their excellent, yet underrated, 1991 album “Trompe le Monde.”


1 Comment

  1. Definitely a related note; the song was named in 1991 before the internet…impressive.

    That mountain looks like it has had a few hundred million years of erosion. I wonder how much bigger it was?

    Liken how eclectic your IFOD’s are.

Subscribe To The IFOD

Subscribe To The IFOD

If you'd like to subscribe to get email notifications when there is a new post, please enter your email below. You can unsubscribe at any time.

You have Successfully Subscribed!

Share This