Mars is hit by meteoroids more often than previously thought
Available online :
• Two researchers from ISAE-SUPAERO have participated in new discoveries based on data from the seismometer sent to Mars during the InSight mission.
• One of the main objectives of InSight was to measure seismological tremors on the Red Planet.
A recent study led by Ingrid Daubar, a researcher at Brown University (USA), reveals that the frequency of space rocks hitting Mars is higher than previously estimated. It also detects two of the largest impacts ever observed by scientists on the Red Planet. The scientific paper, published very recently in the journal Science Advances, states impact rates that could be two to ten times higher than previous estimates, depending on the size of the meteoroids.
The research team includes two teacher-researchers from ISAE-SUPAERO, Raphaël Garcia and Alexander Stott. They used the seismometer onboard the InSight mission to identify eight new meteoroid impact craters that had not previously been seen from orbit.
Prior to this, new impacts on Mars were identified by before-and-after images taken by cameras orbiting the planet. The seismometer made it possible to identify and detect these impacts, many of which could have gone unnoticed. Ingrid Daubar and the research team analysed the seismic signals emitted by InSight, then compared these seismic data with images taken by NASA’s Mars Reconnaissance Orbiter.
A better understanding of meteorite activity levels
"We used the impacts recorded by the InSight seismometer and orbital imagery on Mars to carry out a statistical analysis of the data," explains Alexander Stott, a researcher at ISAE-SUPAERO and co-author of the scientific article. "This makes it possible to determine the frequency with which impacts occur over the whole planet and therefore to better understand the level of meteorite activity."
These results could change our current understanding of the distribution of craters on the surface of Mars, but also on other planets.
"The increased estimate of the flow of meteorites impacting Mars has led us to increase the risk of an asteroid impacting the Earth", comments Raphaël Garcia, professor of planetary geophysics and co-author of the scientific article, who has been involved for several years in the development of the seismometer and the analysis of mission data at ISAE-SUPAERO.
"To this end, the asteroid missions led by NASA, JAXA and, very soon, ESA as part of the HERA programme, are providing essential information to protect our planet should an asteroid be discovered on a collision course with the Earth in the future. The scientific community is also supporting plans for missions to visit the Apophis asteroid before it passes close to Earth in 2029, in particular the RAMSES project currently under discussion at ESA".
An international team
Alongside researcher Ingrid Daubar from Brown University, researchers from the Institut Supérieur de l’Aéronautique et de l’Espace, Oxford University, Imperial College London, the U.S. Geological Survey, ETH Zürich, the University of Arizona, NASA’s Jet Propulsion Laboratory and Université Paris Cité took part in the study. This work was supported by NASA, CNES, the French Space Agency and the British Space Agency.