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NASA’s InSight lander has detected earthquakes on Mars that originate primarily from one region: Cerberus Fossae.
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Scientists evaluating these earthquakes have found evidence that there is molten lava deep within Mars.
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Current magma on Mars would change scientists’ understanding of the planet’s history and interior.
Scientists have long thought Mars was dead – in a geological sense.
Of course, the planet is dotted with volcanoes and there are ancient lava flows in some places. But the cold, arid world seemed to have lost its volcanic fervor long ago.
But now, using a seismometer on NASA’s InSight lander, scientists have discovered the first evidence of molten lava deep below the Martian surface.
The presence of active lava could alter scientists’ understanding of the history of Mars – from its formation, to when it may have supported microbial life, to the loss of its atmosphere and the cold rock it is today. It also explains how scientists understand rocky planets beyond our solar system, including those that could harbor life of their own.
A series of earthquakes on Mars allowed scientists to identify the potential lava hotspot. Unexpectedly, most large earthquakes originated from this location.
“We found something that was really inconsistent with everything we thought was true,” Anna Mittelholz, planetary scientist on the team of researchers behind the discovery, told Insider.
Mittelholz recalled the words of his team’s principal investigator, in reference to the shaking of scientists’ beliefs: “Oh no, we broke Mars.”
Mars’ largest earthquakes point to an underground chamber of magma
InSight has detected more than 1,300 earthquakes on Mars since it landed on the Red Planet in 2018. To the surprise of scientists, the strongest tremors all came from a region full of faults, called Cerberus Fossae.
In a paper published Thursday in Nature Astronomy, researchers analyzed 20 of these large earthquakes. Seismic waves carry information about every part of Mars they pass through on their way to InSight. The researchers found that some seismic waves travel much slower than expected.
“The only answer that seemed logical with this observation is that the region must be hot,” Mittelholz said.
This indicates the presence of molten lava, or “magma”, deep below the surface of Cerberus Fossae. This moving or cooling magma is likely what creates these earthquakes, according to Mittelholz, since the rumblings come from 14 to 50 kilometers below the Martian surface, where scientists suspect the magma chamber is.
“It’s possible that what we’re seeing are the last remnants of this once active volcanic region or that magma is currently moving east towards the next eruption location,” said Simon Stähler, who led the study. , in a press release.
The movement is also likely to cause smaller earthquakes at the surface level, breaking up and moving around the planet’s crust in this region.
“We are quite confident that there is volcanic activity there. It is very difficult to explain the data any other way. ?” said Mittelholz.
InSight embeds the only seismometer ever placed on Mars. It’s just a station in one place, and it can’t detect small earthquakes that happen far away or on the other side of the planet. Scientists therefore have limited information about seismic activity on Mars and any other potential hotspots for earthquakes or magma. To get a global picture of earthquakes and volcanic activity on Mars, NASA would need to send more seismometers to the Red Planet.
This Volcanic, Earthquake-Prone Region of Mars Is a Mystery
Spacecraft orbiting Mars have imaged numerous fault lines along its surface – regions where subterranean tremors are clearly disturbed – so scientists expected InSight to detect earthquakes from many different places.
But Mars surprised them. Almost all earthquakes so far originate from Cerberus Fossae.
“I think it’s going to take some understanding of what it actually means and why it is. What’s so special about Cerberus Fossae? I wouldn’t say it’s what we expected it to be. see,” Mittelholz said.
InSight is running out of power as dust collects on its solar panels. Its mission to Mars will probably end before January 2023. Then there will be no seismometer on Mars to gather new information about the deep structures of the planet.
“I think this InSight data set will be around for a while. There’s so much data coming in all the time that it’s actually hard to fully take in all of the information in it,” Mittelholz said, adding: “So I think a lot of studies will come out of this, even after InSight stops working.”
Read the original article on Business Insider
