Hotspot volcanoes

Space volcanoes: origins, variants and eruptions

Volcanoes represent some of Earth’s most interesting and violent geographic features, a force of destruction and creation. However, volcanic activity is not limited to our planet, and space volcanoes are often found on other planets and moons.

In our solar system, the moon and Mars are rich in evidence of volcanoes and fiery volcanic activity, while other bodies have volcanoes that spit ice from their frozen vistas.

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 their source, according to San Diego State University. (opens in a new tab).

A recent Chinese mission to the lunar surface – the Chang’e-5 lander – returned lava that suggests Earth’s main natural satellite has been volcanically active more recently than previously thought.

The sample taken from Oceanus Procellarum on the near side of the moon, previously associated with recent volcanic activity, suggests volcanism just two billion years ago, a billion years later than previous estimates.

Volcanoes on Mars

Aside from the Earth, the planet whose humanity has studied the geology most intensely is Mars. This led to the discovery that the Red Planet is home to even more volcanic features than our planet, according to Arizona State University (opens in a new tab).

Chief among these is Olympus Mons, the tallest volcano in the entire solar system at twice the height of Mount Everest. It is surrounded by a plethora of other massive volcanoes.

In addition to this, other volcanoes on Mars include Elysium, Syrtis Major, and a group 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 it happened is something astrogeologists are still trying to figure out.

The volcanoes of Tharsis – the location of Olympus Mons – have 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 flares fading 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 once 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.

Olympus Mons compared to Arizona

An image comparing the size of the largest volcano in the solar system, Olympus Mons, to that of Arizona. (Image credit: NASA)

Volcanoes on other planets

Many other planets in the solar system have been linked to volcanic activity, most of them occurring when the solar system was young and violent.

The planet closest to Earth, Venus, has lava flows that cover up to 90% of its surface. Venus has up to 1,600 major volcanoes and could have up to a million smaller equivalents.

What is uncertain is whether the planet is still volcanically active. Although we haven’t yet seen a volcano erupt on any other planet, Venus is shrouded in thick clouds of sulfuric acid, making long-range observations difficult. Visiting the planet with a probe is complicated by its intense pressures and temperatures.

The images captured by the MESSENGER mission have shown that the surface of Mercury has been shaped by volcanic activity. Lava flows on the planet closest to the sun have been dated between one and two billion years. This means that volcanic activity continued long after Mercury was formed around 4.5 billion years ago.

For active volcanoes, look beyond the planets of the solar system to its moons.

volcanoes on the moons

According to an article (opens in a new tab) by NASA, the most volcanic body in the solar system is Io, one of Jupiter’s moons, this activity is caused by the enormous gravitational influence of the gas giant warping the tiny moon.

Not only does Io have volcanoes spouting hot lava, but the Jovian moon is also home to cryovolcanoes. These ice volcanoes that occur on planets and moons far from the sun emit cold, liquid or frozen gases like water, ammonia or methane.

Io is punctuated by hundreds of volcanic vents, many of which shoot jets of frozen gas hundreds of miles into Jupiter’s atmosphere.

Cyrovolcanoes were first observed on one of Neptune’s moons, Triton, when the Voyager 2 spacecraft spotted five-mile-high plumes of nitrogen during its flyby of the Neptunian system in 1989.

These eruptions are caused when solar radiation heats the nitrogen beneath Triton’s surface, vaporizing it, causing it to expand and eventually erupt from the icy surface of the Neptunian moon. Eventually, this material condenses and falls to Triton’s surface, giving it a smooth, snow-covered surface.

In 2005, the Cassini spacecraft observed jets of ice (opens in a new tab) released from the south polar region of Saturn’s moon Enceladus. Cassini actually walked through one of these eruptions discovering that it was mostly water vapor with some nitrogen, methane and carbon dioxide.

Exoplanet Gliese 1132 b

The exoplanet Gliese 1132 b developed a second atmosphere due to volcanic activity. (Image credit: NASA, ESA and R. Hurt (IPAC/Caltech))

Volcanoes beyond the solar system

Of course, there’s no reason to believe that volcanoes are limited to our solar system. The more astronomers explore planets around other stars, the more evidence they find of violent volcanic activity on those planets.

In 2017, Cornell researchers suggested that searching exoplanets for volcanic sources could improve our chances of finding life elsewhere in our galaxy.

The team suggested that rather than trying to search for life under 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 spotting telltale signs of life scattered throughout the atmospheres of these worlds.

The largest volcano in the solar system

Rising nearly 16 miles high with a diameter of 374 miles as wide as the state of Arizona, Olympus Mons is not only the tallest mountain on Mars, it’s also the tallest in the system. solar.

About 100 times larger than Earth’s largest volcano – Mauna Loa – Olympus Mons is an extinct volcano that sits in a field of other large volcanoes called the Tharsis region on Mars.

Like Hawaiian volcanoes, this Martian example is a shield volcano, meaning it is low and wide with swallow-like slopes. The reason for Olympus Mons’ enormous size is theorized to be the result of the difference between the plates of Mars and Earth.

On Earth, as hot spots remain stationary, crustal plates flow over them, which means new volcanoes form and older ones die out. On Mars, however, the hotspot remains stationary, but so does the plate. This leads to lava accumulating in a single large volcano rather than having its volume spread over several.

Additional Resources

The 20-year-old Cassini mission spotted ice volcanoes on Cassini. You can read more about his other important discoveries on NASA’s Cassini webpage (opens in a new tab). Also, to learn more about 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).

“The active volcanoes of 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)“. The National Air and Space Museum (2022).

“Olympus Mons (opens in a new tab)“. NASA Mars Exploration Program. Atlas of Mars.

China’s Lunar Voyage Reveals Surprisingly Recent Volcanic Activity (opens in a new tab)“, O’Callaghan, J. Nature (2021).