Three-dimensional images of a profile of a subsurface layer of the Martian soil reveal new structures in polar caps of the Red planet, including before bedded structure inaccessible to observations, larger, than was considered, deposits of crystal carbon dioxide in the southern polar cap and cotyloid structures which can represent the shock craters located in both polar caps. This information will help scientists to understand more deeply climate changes on Mars and can give them the chance to define an age of polar caps without use of climatic models. These three-dimensional images were made on the basis of the data collected by means of the Shallow Radar tool (SHARAD) established onboard the spacecraft of NASA Reconnaissance Orbiter (MRO) for more than 2000 orbits around the Red planet.
Earlier many important discoveries on the basis of separate pictures of profiles of subsurface layers of the Martian rocks received by means of the SHARAD tool were already made, however now the three-dimensional map is made almost for all volume of interiors of both polar caps.
The main method of assessment of an age of the structures located on the surfaces of planets of Solar system is based on statistical data on quantities of shock craters therefore the cotyloid structures found by researchers during the analysis of these three-dimensional images which can be shock craters have to help to define an age of the Martian polar caps by means of this method. Now the age of almost all structures on the surface of the Red planet is estimated by means of the method based on the analysis of distribution of shock craters, and only polar caps do not give in to such assessment – their age is estimated by means of the numerical models reflecting climate changes in the planet in the past. Therefore the results of the analysis of new three-dimensional radar images of interiors of polar caps revealing number of estimated shock craters in them will allow to use more precise method for assessment of an age of polar caps and to calibrate on it the method described above based on the analysis of climatic models.
