Following two large meteorite impacts on Mars, near-surface seismic waves have been recorded for the first time on a planet other than Earth.
Following two large meteorite impacts on Mars, near-surface seismic waves have been recorded for the first time on a planet other than Earth. The data, analysed by an international team involving University of Oxford researchers, has revealed valuable new information about the structure of the Martian crust. The results have been published today as two papers in the journal Science.
On 24 December 2021, highly unusual seismic waves were recorded by the NASA InSight lander, which has been recording seismic activity (or ‘marsquakes’) on the Red Planet since November 2018. To investigate the potential source, the InSight Science Team examined aerial photographs captured by high resolution cameras on NASA’s Mars Reconnaissance Orbiter. Images taken by the orbiter between 24 and 25 December 2021 revealed a large impact crater about 3,500 kilometres (2,200 miles) from InSight. Using the same method, the researchers then re-examined older data recorded by the lander to investigate another unusual seismic wave recorded during September 2021. This was mapped to a slightly smaller crater just under 7,500 kilometres (about 4,700 miles) from InSight.
Dr Benjamin Fernando (Department of Physics and Department of Earth Sciences, University of Oxford), co-chair of the Impacts Theme Group for InSight, said: ‘These are the biggest fresh craters we have ever seen form anywhere in the Solar System. The larger one is around 150 metres across (about one and a half times the size of Trafalgar Square) and the blast zone is around 35 kilometres across – this would cover most of the area inside the M25.’
Read more at University of Oxford
Photo Credit: AlexAntropov86 via Pixabay
