Even though Mars’ atmosphere is known to us, its anomalous behavior is still a mystery. In the initial reports from the Mars Rover, Curiosity, it was found that the amount methane in the atmosphere kept on changing throughout the year. As per the recent reports, the oxygen levels near the Gale crater have been observed to be fluctuating. Curiosity is currently on its way to foot of Mount Sharp.
Along with collecting the data from the Mars’ crust, it takes readings from the martian atmosphere to amount the seasonal changes. Its been on Mars since 2013, i.e., 3 Mars years, and through these vast sets of readings, scientists have concluded the abnormality in the behavior of oxygen levels. The martian atmosphere contains 95 percent carbon dioxide by volume, 2.6 percent of molecular nitrogen, 1.9 percent of argon, o.o6 percent of carbon monoxide and meager 0.16 percent of oxygen. As against this, earth’s atmosphere contains approximately 78 percent of nitrogen, 21 percent of oxygen, and rest one percent are the remaining gases. Throughout the year, atmospheric pressure changes on Mars. Carbon dioxide freezes over the pole on the winter atmosphere causing a pressure drop across the winter hemisphere. In spring season, when this polar cap melts, causing an increase in pressure. Initially this trend is followed and letter on the evens out. This trend is followed in both the hemispheres due to redistribution of gases. As per this phenomenon, all the other gases should follow the same trend. But it is only true for argon and nitrogen; oxygen, along with methane, does not follow this trend.
The amount of methane and oxygen varies by 30 percent and 60 percent repspectively during spring time. This was deduced by the Quadrupole Mass Spectrometer instrument on the Curiosity rover. According to scientists, this can either occur by geological processes or by organic matter. This mystery will be solved when the Mars 2020 rover will start looking for fossils during its mission.