Despite being our close neighbour, Mars is an enigma that still holds a lot of mysteries that we don’t know much about. NASA’s High-Resolution Imaging Experiment, which is part of the space agency’s Mars Reconnaissance Orbiter, captured an image of the northern plains of Arabia Terra on the red planet which shows craters containing mysterious deposits with curious shapes and distribution.
Interestingly, the deposits are only found in craters that are larger than 600 meters in diameter and are absent from craters that measure 450 metres or less. Also, these deposits are only there on the south sides of the craters and are absent in the north. The deposits have radial striations that are formed by small bright ridges and also have horizontal laminations that could be terraces.
“We suspect that these features formed by sublimation of ice-rich material. The terraces might represent different epochs of sublimation. Perhaps the larger craters penetrated to a water table between 45 and 60 meters below the surface and were flooded after formation,” wrote Paul Geissler of the University of Arizona in a University of Arizona announcement.
Earlier this week, NASA released the sound of a dust devil on Mars. The space agency’s Perseverance Rover’s microphone happened to be turned on by chance while a whirling tower of red dust passed directly overhear. The audio recording contained 10 seconds of rumbling winds of up to 40 kilometres per hour along with the pinging sounds of thousands of dust particles hitting Perseverance.
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The audio was released in the weeks after Perseverance bottled up two dust samples from the Martian surface. Unlike the samples collected by the rover previously, which were rock samples, the two new samples were taken from a pile of wind-blown sand and dust from a small “dune” One of the two new samples will be considered for deposition on the Martian surface so that they can be returned to Earth as part of the agency’s Mars Sample Return campaign.