Marsquakes Are Moving Faster Than They Should and It’s Not Clear Why
In 2021 and 2022, NASA’s InSight lander picked up the tremors coming from the depths of Mars. These Marsquakes were quickly linked with orbital images revealing fresh craters. This was no coincidence: the temblors were caused by Martian impacts.
Now, researchers have connected 49 seismic events to impact craters, proving that meteorite strikes leave distinct seismic signatures on Mars. In the process, they also showed that seismic waves travel much deeper on Mars than expected, posing new questions about the Red Planet’s geology.
Visualization of two large, newly discovered co‐InSight impacts located near Cerberus Fossae. Image credits: Bicker et al (2025) / Geophysical Research Letters.
On Earth, most earthquakes result from plate tectonics — the slow movement of giant crustal plates that grind, slip, or collide. When this happens, they release seismic waves that propagate through the subsurface. Mars, however, lacks plate tectonics. So marsquakes must come from different sources, like meteorite impacts or the Cerberus Fossae fault system, which formed when the planet’s crust was pulled apart.
While quakes can be pretty devastating, they can also be useful. Seismic waves are the best tool scientists have to peer inside a planet, especially since we can’t drill into the Martian mantle or core. When a quake or impact occurs, it generates P-waves (primary waves) and S-waves (secondary waves) that travel through different layers at varying speeds. By analyzing how these waves reflect, refract, or slow down as they move through the crust, mantle, and core, scientists can determine the composition and density of each layer.
Until now, researchers assumed that most marsquake waves were trapped in the crust, traveling slowly along a “waveguide” instead of penetrating deeper layers. However, two studies challenge this idea.
“We used to think the energy detected from the vast majority of seismic events was stuck traveling within the Martian crust,” said InSight team member Constantinos Charalambous of Imperial College London. “This finding shows a deeper, faster path — call it a seismic highway — through the mantle, allowing quakes to reach more distant regions of the planet.”
Faster than expected
The fastest route for a seismic wave isn’t always the direct one. These waves have different velocities in different layers. Think of it this way: if I asked you to get to the other side of a lake, it could be faster to run around it rather than swim across it. Similarly, seismic waves bend and speed up as they travel through denser layers of a planet’s interior. So instead of moving in a straight line through the crust, which is less dense, some waves dive into the mantle, where they propagate at higher velocities, then curve back upwards towards the surface, reaching the seismometer. These waves can arrive faster than waves coming on a direct path, and this is what researchers observed in these studies.
When researchers matched seismic events to fresh impact craters using orbital images, they found that some waves arrived sooner than expected. Scientists pieced together seismic data with satellite imagery of Mars, correlating multiple impact events with seismic waves. They used a machine-learning analysis to catalog 123 fresh impact craters with their corresponding seismic events. In some instances, they were able to correlate mere pixels on visual data with craters and marsquakes.
Professor Tom Pike from the Imperial team explains:
“These results show the power of looking deeply into multiple datasets from Mars. Without the seismic data, we would not have known where to look for an impact in the orbital images, and without the orbital images, we would not have been able to locate the source of the seismic energy we detected with InSight.
“The fact that we have been able to identify an impact in a single pixel of MRO’s low-res orbital camera, intended for daily weather monitoring, shows just how essential it is to combine these large datasets. The power and speed of AI means we have been able to find the proverbial needle in the haystack!”
A camera on the robotic arm of NASA’s InSight captured the lander setting down its Wind and Thermal Shield on Feb. 2, 2019. The shield covered InSight’s seismometer, which captured data from more than 1,300 marsquakes over the lander’s four-year mission. Credit: NASA/JPL-Caltech.
We’re gonna need to update our Mars models
With this approach, they found several marsquakes that originated farther than initially believed. This means they must have traveled faster, through a deeper layer. This means that first of all, Mars suffers more meteorite impacts than we thought, it’s just that they’re small, and without the temblors, we wouldn’t have found them. Secondly, we need to update our seismic velocity models of Mars’ interior.
“Done manually, this would be years of work,” said InSight team member Valentin Bickel of the University of Bern in Switzerland. “Using this tool, we went from tens of thousands of images to just a handful in a matter of days. It’s not quite as good as a human, but it’s super fast.”
Future missions could place multiple seismometers across Mars to pinpoint quakes with greater accuracy. ESA’s ExoMars mission and future NASA-led initiatives may deploy a seismic network — similar to Earth’s global earthquake monitoring system.
But this isn’t just important for Mars. Similar seismic methods are being used on the Moon (Artemis program) and could be applied to icy moons like Europa, where seismic waves could detect underground oceans.
As for Mars, the jury’s still out on exactly what’s happening inside its crust and mantle. Could there be residual volcanic activity beneath the surface or something that accelerates waves in the deeper layers? Could some underground reservoirs exist in regions where seismic waves slow down? These are the questions that researchers hope to answer in future years.
