Methane (CH.) on Mars4), some see it. Others don’t see it. And it has puzzled astronomers for many years. But in the end, the researchers offer an explanation. The detection will strongly depend on the time of day on which the measurement is taken.
This happened for the first time in 2004. methane (CH4) was seen on Mars by a European probe. And if the search so excited , that’s because, on Earth, it’s exclusively – those that help animals digest – those that generate methane: life, in other words. So, even though geological processes can also produce it, finding traces of methane on Mars is exciting. especially since I will have a lifetime A resident of Mars only about 300 years old. If our equipment detects any, it may only be the result of a relatively recent injection.
What is kept here? But, beyond the riddle ofOn Mars, astronomers have for many years been up against another mystery. Because if, in addition to Mars Express, the Curiosity rover ( ) has repeatedly detected methane above the surface of Gale Crater, European mission ExoMars Trace Gas Orbiter (TGO) has never been able to confirm the presence of this gas in large quantities in the atmosphere.
Of course, the amount of methane detected by Curiosity is very small. Less than half a billion (ppb). The equivalent of a pinch of salt in an Olympic swimming pool. All the same with a concentration peak that can reach 20 ppb. “But when the European team announced that they had not seen methane, I was certainly shocked”, recalls instrument head Chris Webster tunablespectrometer ( ) de Curiosity, . Because TGO was designed to be the gold standard for gas measurement .
What if Curiosity and TGO are both correct?
Researchers initially doubted the curiosity of producing CH.4 that he found out. He analyzed it from every angle: the way it crushes rocks, the way its wheels wear down, etc. To conclude without appeal that the measurements taken by the rover are accurate.
And again, planetary scientists suggested that there was no mystery or error. Both that curiosity and TGO could be right. The observed differences in measurements can only be related to the time at which these measurements are made.
The researchers specify that the TLS instrument used by Curiosity to measure methane may only operate at night. it’s really greedyand wait to wake up, until all other devices are turned off. But at night the atmosphere of Mars is quite calm. Methane seeping out of the ground is likely to be deposited near the surface and will be detected by Curiosity.
How can methane disappear from the atmosphere of Mars?
TGO, for its part, needsTo find traces of methane about five kilometers above the ground. but There was a stir in the atmosphere of the day. And at night, concentrated methane at ground level is found diluted in the atmosphere a few hours later. There is a suspicion of not being knowledgeable at the level.
Astronomers have recently confirmed this. they have collected exceptionallyfor day measurement. And the TLS tool could not be found … find anything! So this solves the problem. At least in appearance. Because even if methane is continuously leaking out of Martian soil and has a lifetime of about 300 years in the atmosphere, it should still accumulate enough to detect a TGO.
So it remains to be understood what destroys the methane in the Martian atmosphere. Perhaps very low-intensity electric shocks induced by Martian dust. or a. action ofis abundant on the surface which will destroy CH4 before reaching the upper atmosphere. Experiments continue.