Sad news: it's probably not about alien microbes
Artistic impression of the Mars Express spacecraft against a real image of the Martian surface. Image credit: ESA / ATG medialab; Mars: ESA / DLR / FU Berlin
The Mars Express spacecraft from the European Space Agency captured a large puff of methane from the orbit, confirming a previous gas detection on the red planet by the US Curiosity rover.
The signs of the hydrocarbon molecule arouse enthusiasm because there is a possibility that it could be produced by biological processes and, therefore, there is some kind of alien life. On Earth, gas is created as a byproduct of anaerobic respiration by a group of ancient single-celled microbes, but it can also be created by geological processes.
There was excitement at NASA in 2013 when Curiosity detected four huge peaks of methane. Since then, ESA scientists have reviewed the readings compiled by Mars Express between 2012 and 2013, a time when NASA's curiosity exploration vehicle began to explore the Martian surface.
This week we were told that Euro eggheads discovered that their spacecraft actually detected methane a day after the US rover did it in June 2013. At that time, Curiosity was circling around the Gale crater and Mars Express flew on the same place. as well. The two consecutive readings that originated in the same region have sent languages to the community dressed in lab coats.
"In general, we did not detect any methane, apart from a definitive detection of approximately 15 parts per billion by volume of methane in the atmosphere, which turned out to be a day after Curiosity reported an increase of approximately six parts per billion," Marco said. Giuranna, lead author of the results published in Nature Geoscience, and researcher at the National Institute of Astrophysics and Planetology, Italy.
"Although the parts per billion in general mean a relatively small amount, it is quite remarkable for Mars, our measurement corresponds to an average of approximately 46 tons of methane that was present in the 49,000 square kilometer area observed from our orbit." additional.
The Martian atmosphere is a difficult environment to survive. It is constantly hit by the sun's rays, so the methane molecules will not last long, as they are destroyed when they collide with the high-energy photons and electrons emitted by the Sun. The measurements made by the spacecraft mean that the gas it was recently expelled, even if it had been millions of years ago.
Unfortunately there are no signs of alien microbes in the simulations.
Although it is the first time that two independent measurements made by a spacecraft and an exploration vehicle seem to coincide with each other, the results do not provide many suggestions on how methane was produced.
Then, researchers turned to simulations instead. Now it seems that the amount of methane detected seems to show that the source of the gas is not hidden around the Gale crater.
"Our new Mars Express data, taken a day after Curiosity's registration, changes the interpretation of where the methane originated, especially when considering global atmospheric circulation patterns along with local geology," Giuranna said. "Based on the geological evidence and the amount of methane we measure, we believe it is unlikely that the source is located inside the crater."
Computer simulations that show the probability that certain regions of the Martian surface emit methane. They were based on measured data, atmospheric processes and the effect of methane exit from the rocks.
Boffins may have found something more salty than the tears of Brexit Brits this week: underground pools of water on Mars
They demonstrated that it was possible that trapped methane could seep through meteor impacts that hit the Martian surface and release gas. Other processes, such as cracks in permafrost, could also release methane into the air.
"Our results support the idea that the release of methane on Mars could be characterized by small and transient geological events rather than a global presence that is constantly replenished, but we must also better understand how methane is removed from the atmosphere and how to reconcile the Express of Mars. " data with the results of other missions, "said Frank Daerden, co-author of the article and researcher at the Royal Belgian Institute of Space Aeronomy.
Scientists hope to badyze more data and see if other sources, such as the ExoMars trace gas orbiter, could also have detected methane. The ExoMars Trace Gas Orbiter was launched in 2014 and just began to conduct scientific observations this month. ®
Become a pragmatic security leader