Volcanoes on Mars may be more active than previously believed, according to data from NASA’s InSight mission. They also may be the reason why the Red Planet spins a little faster each year.
Back in 2023, data from NASA’s InSight mission revealed that Mars was spinning at an accelerating rate and that its days were getting minutely shorter. Why this was happening was a bit of a mystery to scientists.
At the time, according to Live Science, researchers hypothesized that ice accumulation at the planet’s poles may have been causing a slight change in how the planet distributed its mass. This, in turn, was enough of a subtle change to affect the Red Planet’s rotation.
Another possible reason cited was the fact that the core of Mars, while smaller than Earth’s, is larger in proportion to the planet. It is also not uniform. It has regions of higher or lower density that could be affecting the planet’s rotational speed.
Scientists think that volcanoes once considered dead may still be bubbling under the Martian surface
Now, however, a new study published in the Journal of Geophysical Research: Planets suggests a huge plume of buoyant rock beneath the crust of Mars may be the cause.
“The Martian surface is so old and shows all these complex but largely not well understood process[es], which I think we can start to unravel by combining interior with surface,” Bart Root, an assistant professor of planetary exploration at the Delft University of Technology in the Netherlands and first author of the study, told Live Science in an email. “Understanding Mars will help in understanding our solar system, as its history is laid out on the red soil.”
Since Mars does not have plate tectonics, as Live Science puts it, lava from “ancient active volcanoes just sits there, piling up and building far bigger structures over time.”
In an effort to understand why the Tharsis volcanic province is so prominent on one side of Mars, researchers used InSight data to run computer simulations. They found a “negative mass anomaly” that may indicate future volcanic activity on Mars.
“The negative or light mass anomaly will move upwards and hit the lithosphere of Mars, introducing melt pockets that have the potential to penetrate the crust and erupt as volcanoes,” Root said.
It is this plume of material that may explain why Mars is spinning faster and faster over time.
Root compared this process to someone spinning in a desk chair while holding heavy books. If the books are pulled inward, the spin speeds up. Mars may be doing something similar with this less-dense material.
“A negative mass flowing upwards means something heavier needs to go down, and because the mass anomaly is located on the equator of Mars, this means the heavier mass is going closer to [the] rotation axis, hence a speed up,” Root said.