Europe 1 with AFP 06:37, October 28, 2022
On December 24, 2021, a meteorite hit Mars, causing tremors of magnitude 4. These were detected by the Insight probe and its seismometer, which landed on the planet almost four years ago.
An audio recording of the earthquake, obtained by accelerating the vibrations collected by the seismometer in order to make them audible, was released by NASA.
Scientists who observe the planet Mars received a remarkable Christmas present last year.
On December 24, 2021, a meteorite hit its surface, causing tremors of magnitude 4. These were detected by the Insight probe and its seismometer, which landed on Mars almost four years ago, some 3,500 kilometers from the place of the impact.
But the origin of this Martian tremor was only confirmed later, by the spacecraft called Mars Reconnaissance Orbiter (MRO).
In orbit around the planet, it took pictures of the newly formed crater within 24 hours of the event.
"Biggest ground meteorite impact listened to"
The image is impressive: blocks of ice were thrown on the surface, and a crater about 150 meters in diameter and 20 meters deep was dug - the largest ever observed since the commissioning of the orbiter MRO, 16 years ago.
Even though meteorite impacts on Mars are not uncommon, "we never thought we'd see something this big," Ingrid Daubar, who works on the Insight and MRO missions, told a news conference on Thursday. .
Our @NASAInSight Mars lander "heard" seismic signals while our Mars Reconnaissance Orbiter captured images of the impact crater made by this Martian meteorite.
To make the sounds audible, the data was sped up 100 times.
Listen: https://t.co/X00C5ca2NQ
— NASA (@NASA) October 27, 2022
The researchers estimate that the meteorite itself must have been around 12 meters - which on Earth would have caused it to disintegrate in the atmosphere.
"It is quite simply the biggest meteorite impact on the ground that has been listened to since we have been doing science with seismographs or seismometers", explained to AFP Philippe Lognonné, professor of planetology who participated in two studies from these observations, published Thursday in the journal Science.
An audio recording of the earthquake, obtained by accelerating the vibrations collected by the seismometer in order to make them audible, was released by NASA.