NASA's curiosity rover returned some seriously surprising data to Earth earlier this year, with indications of elevated methane levels that were difficult to explain. Subsequent tests have tried to determine the cause of the reported higher than expected, but scientists have not yet received a definitive answer.
Now, as methane issues continue to rotate, scientists studying the behavior of Mars gases have noticed that oxygen on the Red Planet also acts much differently than on Earth. The observations were made at the Galle Crater, which the rover had called home since it landed there in 2012.
Curiosity "breathes" Mars air and analyzes it to determine the levels of the various types of gases that are present. On Earth, the background levels of some gases rise and fall with the seasons, and the same seems true of Mars, but only to a point.
Mars air is largely carbon dioxide. In fact, 95% of the gas that Curiosity absorbs during its tests is CO2. The remaining 5% is a mixture of nitrogen, argon, oxygen and carbon monoxide. By plotting the levels of these gases over a full Martian year, the scientists noticed anomalies in the amount of oxygen compared to other gases.
In this environment, scientists have discovered that nitrogen and argon follow a predictable seasonal pattern, wax, and reductions in concentration throughout the year, depending on how much CO2 is in the air. They expected oxygen to do the same. But it did not happen Instead, the amount of gas in the air rose in the spring and summer by as much as 30% and then dropped to levels predicted by the known chemistry in the fall.
The fact that oxygen levels vary as wildly as they do. is important because it hints at the as yet undiscovered work processes on the planet's surface. In order for the oxygen levels to notice a significant jump up and then drop dramatically, something has to create it and then another uses it.
"We are struggling to explain it," Melissa Coach at NASA's Godard Space Flight Center. "The fact that oxygen behavior does not repeat itself perfectly every season makes us think that this is not a problem with atmospheric dynamics. This must be some kind of chemical source and sink that we cannot yet account for. "
Before you start dreaming of an underground race of Martian monsters, it's important to know that this is not a smoking weapon for Mars, in fact it is far from it. There are natural processes that can generate oxygen in the absence of life, and since we have not yet found evidence of life on the Red Planet, but cannot yet rule it out, scientists are considering all possible variants.