Volcanoes represent some of the most interesting and violent geographical features on Earth, a force for destruction and creation. However, volcanic activity is not limited to our planet and space volcanoes are often found on other planets and moons.
Within our solar system, the moon and Mars are rich with evidence of volcanoes and fiery volcanic activity, while other bodies possess volcanoes that drag ice from their frozen views.
Volcanoes on the moon
Now volcanically inert, the moon’s surface once hosted spectacular eruptions that created lava flows that extended up to 750 miles from its source, according to San Diego State University (opens in a new tab) .
A recent Chinese mission to the lunar surface – Camping Chang’e-5 – returned lava that seems to indicate that the Earth’s primary natural satellite was more volcanically active than previously thought.
The collected sample of Oceanus Procellarum on the near side of the Moon, previously associated with recent volcanic activity, suggests a volcanism as recent as two billion years ago, a billion years later than previous estimates.
Volcanoes on Mars
Apart from Earth, the planet that humanity has studied geology most intensely is Mars. This has led to the discovery that the Red Planet hosts even more volcanic features than our planet, according to Arizona State University (opens in a new tab).
The main one of these is Olympus Mons, the largest volcano in the entire solar system at twice the height of Everest. It is surrounded by a lot of other massive volcanoes.
In addition to this, other volcanoes on Mars include Elysium, Syrtis Major, and a cluster of low-profile volcanic structures near the Hellas impact basin. This basin is the lowest point on Mars and the third or fourth largest known impact crater in the solar system.
Mars appears to be volcanically inactive, but when that happened it’s something astrogeologists are still trying to figure out.
Tharsis volcanoes, the location of Olympus Mons, show few asteroid impact craters, meaning they could be only a few million years old, which is quite young in geological terms.
Mars was clearly very active in its youth, with explosive eruptions that became extinct as it aged. The planet has no active volcanoes, according to the National Air and Space Museum (opens in a new tab), and it appears that most of the heat stored inside the planet has been lost.
It is possible that we are currently simply seeing Mars in a geologically calm period and that volcanism may be restarting on the Red Planet.
An image that compares the size of the largest volcano in the solar system, Olympus Mons, with Arizona. (Image credit: NASA)
Volcanoes from other planets
Many other planets in the solar system have been associated with volcanic activity, most of which occurred when the solar system was young and violent.
The closest planet to Earth, Venus, has lava flows that cover up to 90 percent of its surface. Venus has up to 1,600 major volcanoes and could have up to a million smaller counterparts.
What is not certain is whether the planet is still volcanically active. Although we have not yet seen an erupting volcano on any other planet, Venus is surrounded by thick clouds of sulfuric acid, which means long-distance observations are difficult. Visiting the planet with a probe is complicated by its intense pressures and temperatures.
Images captured by MESSENGER mission have shown that the surface of Mercury was shaped by volcanic activity. It has been dated that the lava flows of the planet closest to the sun are between one and two billion years old. This means that volcanic activity continued long after the formation of Mercury about 4.5 billion years ago.
For active volcanoes, you need to look beyond the planets of the solar system to their moons.
Volcanoes on the moons
According to a NASA article (opens a new tab), the most volcanic body in the solar system is Io, one of Jupiter’s moons, this activity is caused by the tremendous gravitational influence of the gas giant that deforms the tiny moon.
Io not only has volcanoes that drag very hot lava, but the Jovian moon also hosts cryovolcanoes. These ice volcanoes found on planets and moons far from the sun erupt from cold, liquid, or frozen gases such as water, ammonia, or methane.
Io is marked with hundreds of volcanic respirators, many of which explode frozen gases hundreds of miles into Jupiter’s atmosphere.
Cirovolcanoes were first observed on one of Neptune’s moons, Triton, when the Voyager 2 spacecraft spotted five-mile-long nitrogen feathers during its overflight of the Neptune system in 1989.
These eruptions occur when solar radiation heats nitrogen below Triton’s surface, vaporizing it, causing it to expand, and eventually erupting from the icy surface of Neptune’s moon. Eventually, this material condenses and falls back to Triton’s surface, giving it a smooth snow-covered surface.
In 2005, the The Cassini spacecraft observed jets of ice (opens in a new tab) released from the south polar region of Saturn’s Enceladus moon. Cassini actually flew through one of these eruptions and discovered that it was composed primarily of water vapor with some nitrogen, methane, and carbon dioxide.
The exoplanet Gliese 1132 b has grown a second atmosphere due to volcanic activity. (Image credit: NASA, ESA and R. Hurt (IPAC / Caltech))
Volcanoes beyond the solar system
Of course, there is no reason to believe that volcanoes are restricted to our solar system. The more astronomers explore planets around other stars, the more evidence they will find of violent volcanic activity on those planets.
In 2017, Cornell researchers suggested that searching for volcanic sources on exoplanets could improve our chances of finding life elsewhere in our galaxy.
The team suggested that instead of trying to find life beneath the frozen shells of exoplanets, volcanic hydrogen and atmospheric warming could indicate the possibility of life on the surface.
This could, in turn, increase the likelihood of detecting telltale signs of life distributed in the atmospheres of these worlds.
The largest volcano in the solar system
At nearly 16 miles high with a diameter of 374 miles as wide as the state of Arizona, Olympus Mons is not only the largest mountain on Mars, it is also the largest in the solar system.
About 100 times larger than the largest volcano on Earth – Mauna Loa – Olympus Mons is an extinct volcano located in a field of other large volcanoes called the Tharsis region of Mars.
Like Hawaiian volcanoes, this Martian example is a shielded volcano, meaning it is low and wide with swallow slopes. The reason for the enormous size of the Olympus Mons is theorized as the result of how the plates of Mars and Earth differ.
On Earth, while hot spots remain stationary, plates of crust flow over them, meaning new volcanoes form and the older ones become extinct. On Mars, however, the hot spot remains stationary, but so does the plate. This causes lava to accumulate in a large volcano instead of having its volume distributed among many.
Additional resources
The 20-year-old Cassini mission detected ice volcanoes in Cassini. You can read about his other significant discoveries on NASA’s Cassini website (opens in a new tab). Also, for more information on volcanoes on other planets, read this article from the American Museum of Natural History (AMNH) (opens in a new tab).
Bibliography
“Volcanoes (opens in a new tab)” Mars Education at Arizona State University (2022).
“Active volcanoes in our solar system (opens in a new tab)”. Hobart M. King, PhD, RPG. Geology.com (2022).
“Young Volcanoes on the Moon (opens in a new tab)”. NASA Science (2014).
“Exploring the planets (opens in a new tab)”. National Museum of Air and Space (2022).
“Olympus Mons (opens in a new tab)”. NASA’s Mars Exploration Program. Atlas of Mars.
“China’s Journey to the Moon Reveals Surprisingly Recent Volcanic Activity (Opens in a New Tab),” O’Callaghan, J. Nature (2021).