Any Martians reading this should practise ducking and covering.

According to NASA’s Jet Propulsion Laboratory in Pasadena, California, the Red Planet was jolted by a magnitude 5 temblor on May 4, the greatest Marsquake yet detected. The tremors lasted more than six hours and unleashed more than ten times the energy of the preceding quake.

The event was captured by NASA’s InSight lander, which has been exploring Mars’ deep interior since landing on the planet in 2018 (SN: 11/26/18). The tremor most likely began around the Cerberus Fossae region, which is over 1,000 kilometres away from the lander.

Cerberus Fossae is noted for its rockfalls and shattered surface. According to geophysicist Philippe Lognonné, chief scientist of the Seismic Experiment for Interior Structure, InSight’s seismometer, it makes sense that the ground would change there. “It’s an old volcanic crater.”

Marsquakes can be used to examine what lies beneath Mars’ surface, just as earthquakes offer information about our planet’s internal structure (SN: 7/22/21). And, according to Lognonné of the Institut de Physique du Globe de Paris, “a lot can be learned from analysing this whopper of a quake.” “We’ll be able to work on the details because the signal is so good.”