The surface layer of the Martian satellite Phobos is homogeneous in structure and consists of very fine-grained substance. It helped to find out infrared satellite pictures obtained by the space station “Mars Odyssey”. Such studies are needed to solve the problem of the origin of the satellites of Mars, reported on the website of the jet propulsion Laboratory of NASA.
Mars has two satellites, Phobos and Deimos, and their origin still remains a mystery. It is assumed that they could be formed in the Main asteroid belt, and was then captured by Mars; according to other suggestions, Phobos and Deimos were formed from the substances emitted to the orbit of Mars from its surface as a result of collision with a dwarf planet or giant asteroid. To understand the origin of the satellites may help the study of their composition: in particular, in the future we plan to bring soil from Phobos to Earth with the aid of the interplanetary station MMX and then spacecraft “Phobos-Grunt 2”.
However, data on the composition of the surface layer can be obtained with the aid of apparatus operating in orbit around Mars. For more than two years, the station “Mars Odyssey” using the THEMIS (Thermal Emission Imaging System) is monitoring the Phobos in the infrared range with a distance of several thousand kilometers. Comparing the received image with the images of Phobos in the optical range, scientists are trying to determine the rate of cooling and surface temperature in different areas of the satellite, which differ from one another in the illumination of the sunlight that allows us to estimate thermal properties of the soil and, consequently, to determine its approximate composition and structure.
Analysis of collected data showed that the maximum measured temperature of the surface of Phobos was 27 degrees Celsius and the minimum was -123 degrees Celsius. The observed thermal properties of the surface layer of the satellite suggests that it is homogeneous in structure and consists of very fine-grained substance and the main component in the composition of Phobos can be basalt rocks. The station will continue to monitor the companion to help astronomers to create a more complete picture of the properties of the soil of Phobos.
Earlier we told you about how the device “ExoMars” photographed Phobos, and also about where on the moon appeared long “scars”.