olympus mons
February 8, 2017

This incredible Martian volcano once erupted for 2 billion years

Earth volcanoes have nothing on their Martian counterparts, according to a new study published this month in the journal Science Advances which revealed that the Red Planet was once home to an eruption that lasted for more than 2 billion years before finally coming to an end.

Perhaps that shouldn’t come as a complete surprise, given that Mars is also home to the largest volcano in the solar system (Olympus Mons), but as study co-author Marc Caffee, an astronomy and physics professor at Purdue University , said in a statement, “We’ve never seen anything like that on Earth... where something is that stable for 2 billion years at a specific location.”

Despite involving a volcano on a planet millions of miles away, the discovery was actually made by analyzing meteorites found right here on Earth, explained ScienceAlert. Caffee and his fellow researchers found an unusual meteorite in Algeria in 2012 that they dubbed NWA 7635.

NWA 7635 weighed just seven ounces (0.2 kilograms) and was small enough to fit in the palm of a person’s hand, the website explained, but it turned out to be a big deal after dating revealed that it was approximately 2.4 billion years old. That was a surprise, as 10 other meteorites which were part of the same group were found to be just 500 million years old.

Each of the meteorites were determined to have been exposed to cosmic rays for more than one million years, the researchers said. However, due to the age gap between NWA 7635 and the rest of the space rocks, they determined that there had to have been “a steady plume of magma” from “one location on the surface of Mars” for a period of at least 2 billion years, if not longer.

Meteorite may have originated from Olympus Mons

While Caffee’s team knows that the rock came from Mars, they currently do not know which of the planet’s volcanoes was responsible for the prolonged eruption. While it may have come from Olympus Mons, the 17-mile crater that is unequaled in our solar system, the study authors noted that they simply aren’t sure at this time, according to USA Today.

What they do know is that it’s journey to Earth began after something hit the surface of the Red Planet (probably a lava plain or volcano), causing rocks to be ejected into space. Over time, they found their way to Earth where they fell to the ground as meteorites, the newspaper said.

That process likely took several hundred thousand, if not millions of years, the researchers said. Finally, once a handful of the fragments found their way here, they traveled in a perturbed orbit culminating with their impact, where they began to slowly degrade, making it difficult to notice their extraterrestrial origins to all but the carefully trained eyes of astronomers and geologists.

NWA 7635 and the 10 other meteorites discovered along with it by the researchers were a type of volcanic rock called a shergottite and had similar chemical compositions and ejection times, lead author and University of Houston geology professor Tom Lapen said in a  statement. “We see that they came from a similar volcanic source,” he added. “Given that they also have the same ejection time, we can conclude that these come from the same location on Mars.”

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Image credit: NASA