A few years ago, data collected by Mars Advance Radar for Subsurface and Ionosphere Sounding , enabled scientists to state with a high degree of confidence that there was water under the ice cap of the southern pole of Mars, and now those data were used for computer modelling, which showed that there might be layers of hard rock under the ice instead of water.
The MARSIS tool scans the surface of the Red Planet with a high frequency pulse, and by reflecting the signals from layers with different densities, it is possible to learn more about the planet's structure. To process the data obtained, researchers have used methods similar to those used in earlier studies of underwater water bodies in Antarctica, the Arctic and Greenland. After analysing the "wet" and "dry" ice areas in the vicinity of Ultima Scopuli area on the southern pole of Mars, scientists have concluded that there are significant quantities of liquid water hidden under a thick ice cap in this area.
New modelling using Mars Express data showed that satellite signals did not guarantee that there were water bodies in the southern pole of Mars. Scientists assumed that the MARSIS signals were not from water or ice, but from lower-lying geological layers consisting of minerals and frozen carbon dioxide. It was also found that signals of this type were reflected from the surface layers of a defined thickness, regardless of the material they were made of.
Researchers used MARSIS data in computer simulations, which also added layers of ice and other substances, such as basalt layers, formed after volcanic eruptions on Mars in ancient times. The main purpose of the modelling was to determine how they could react to the light-displaced layers of the Martian surface of different densities. Since large accumulations of frozen carbon dioxide on the southern pole of Mars were also included in modelling. An experiment with a layer of carbon dioxide ice and water ice under it showed that the separation of the layers and their thickness determined the intensity of the light reflected by them. Previous studies had shown that such reflection could occur in the scanning of some minerals. This suggested that liquid water was not necessarily necessary to produce such an outcome.
He also believes that the composition of the base layers of the Martian surface is less important than their thickness and area between them, but a new study does not mean that there is no water on Mars, so scientists will continue to look for it.