Atmosphere of Mars slowly decreased to very low concentrations, with no layer detectable above 35 km. The reporting scientists think that the observed polar ozone layers are the result of the same atmospheric circulation pattern that creates a distinct oxygen emission identified in the polar night and also present in Earth's atmosphere. This circulation takes the form of a huge Hadley cell in which warmer air rises and travels toward the south pole before cooling and sinking at higher latitudes. Mars is on a quite elliptical orbit and has a large axial tilt, which causes extreme seasonal variations in temperature amongst the northern
COSPAR international reference atmosphere COSPAR international reference atmosphere The COSPAR International Reference Atmosphere (CIRA) is an empirical model of the atmosphere of Earth. It consists of a set of tables of average air pressures, altitudes and temperatures. The CIRA models are developed by the Committee on Space Research (COSPAR) and have been important for the planning of spaceflight. Orbit determinations and flight planning of the very first satellites proved to be more complicated than expected due to a lack of knowledge on the upper atmosphere. The Committee on Space Research therefore set up a long lasting special project to elaborate a reference model of