Mars is home to numerous intriguing mysteries. Was microbiological life ever present there? Are there any undiscovered “lakes” under the polar cap? A number of craters can be found in the Arabia Terra region in the northern half of Mars. These craters are surrounded by a number of intriguing mysteries.
NASA’s Mars Reconnaissance Orbiter took numerous aerial photographs of Arabia Terra’s craters with its HiRise camera.
The disputed craters “contain unusual deposits with puzzling forms and distribution,” as stated by the HiRise team’s Paul Geissler. CNET reported that researchers at the University of Arizona manage HiRise.
HiRISE 4K: Mineral Exposures in Terra Sabaea— HiRISE: Beautiful Mars (NASA) (@HiRISE) December 20, 2022
This cutout features a portion of an impact crater with a curious shape, perhaps owing to epochs of erosion. (See link for full cutout.)https://t.co/jsgJyrlYgm
NASA/JPL-Caltech/UArizona#Mars #science #NASA pic.twitter.com/9HrRPh7dU3
There are numerous ways to complicate the crater mystery. Geissler claims that the deposits have strata or terrace-like horizontal laminations. Additionally, they have light-emitting ridges. Atypical deposits are only found on the south sides of craters larger than 1,970 feet (600 meters) in diameter. They are absent from smaller craters.
HiPOD: A Fresh Impact Crater with an Odd Shape— HiRISE: Beautiful Mars (NASA) (@HiRISE) April 18, 2022
This odd-shaped hole in Noachis Terra is clearly in impact crater. It has the characteristic raised rim that distinguishes it from pits that have simply collapsed. https://t.co/YwLwR8Zh9Q
NASA/JPL-Caltech/UArizona#Mars #science pic.twitter.com/mkuc1FlaSy
Although the peculiar shapes are somewhat perplexing, there may be a connection to the sublimation of glacial material on Mars—sublimation is the process by which a solid transforms directly into a gas.
Geissler wrote, “The terraces might represent different epochs of sublimation.” It’s possible that the deeper, more substantial craters reached a water table somewhere between 45 and 60 meters below the surface and were flooded after formation.
Ice-crusted rim of Korolev Crater on Mars, clearly made of ice cream. (📷 ESA/Trace Gas Orbiter) pic.twitter.com/bwDc9mkFgJ— Andrew Rader (@marsrader) December 19, 2022
Mars values sublimation a ton. An excellent illustration is the “Happy Face Crater,” a crater in the planet’s icy south polar zone. Over time, sublimating frost has altered the appearance of the crater as well as the smiling face within.