It is possible that a waft of methane found by a Nasa roamer on Mars may have been released from a layer of permafrost containing the bubbles of the gas that was broken by a geological incident, researchers have said.
This is the first time scientists have identified a possible source of methane on Mars, although the scientific community has still to share about whether the gas is actually being produced. the planet at all. Some say that the methane disclosures on Mars are invalid or have come from other sources such as the roamer itself.
On 16 June 2013, instruments on Curiosity recorded a swing in methane in the Gale crater, a 96 mile wide bowl where the rambler landed in August 2012. Since then, he has found evidence of seasonal variations in methane, with levels of the gas rises and falls with summers and Martian winters.
The apparent presence of methane on Mars has triggered intense speculation that the gas could arise from beneath microbial knights, although a brighter explanation points to a reaction between olive rocks and water. The two processes release the gas on the Earth.
In the latest study, Marco Giuranna turned to colleagues at the National Institute of Astrophysics in Rome to a tool on the European Space Agency's Marsbit orbiter to look for more evidence of methane on Mars.
Scientists used a planetary four (PFS) spectrometer of the orbiter to look for methane in and around Gale's crater from December 2012 to July 2014. The instrument only found methane once, on the same day curiosity found the t a sharp spike in the gas.
“Our perception means the first independent confirmation of methane detection,” said Giuranna. “Before our study, methane detections on Mars were not confirmed, either in the place, from orbit, or from ground telescopes, by independent observations.”
While the curiosity explorer measures methane concentration of 5.78 per billion (ppb) in Gale's skin on 16 June 2013, the Mars Express tool recorded 15.5ppb in the atmosphere column above the crater, the scientists report in Nature Geoscience.
In an attempt to find the source of methane, the scientists shared a wide region around the Gale crater into a grid with 250km squares on each side. Researchers at Aeron's Royal Air Space Institute in Brussels used computer models to simulate a million different emissions scenarios in each square. Meanwhile, geologists in the United States and Italy examined the region around the crater about features that could release methane.
“Amazingly, we found that the atmospheric simulation and the geological assessment, performed independently of each other, suggested the same source of methane, which is about 500km to the east of Gale, ”said Giuranna. The location, known as Aeolis Mensae, has a number of geological defects that may have broken the permafrost nearby and released any methane that has been caught inside. Otherwise, meteorites that come in could have broken the ice open.
The study does not speculate about the ultimate origin of methane on Mars, but Giurann said that entering a source was the first step towards a solution. Even if the perpetrator was not the microbes, he said, the gas would make the planet more residential because it could be used as a source of carbon and energy. People could also make use of methane that is held under the planet's soil to make chemicals and rocket fuels.
The results are likely to hinder the debate on the existence of Martian methane. In December, researchers working on the European Space Agency (TGO) Trace Gas Orbiter ExoMars said they had not found any methane in the Martian atmosphere since the spacecraft reached the orbit in 2016. perceptions suggest that methane emissions are very rare and that the gas is rapidly disappearing.
“The findings are somewhat surprising,” said Manish Patel, an OU researcher working on the TGO mission. “Comparing these results with what we see with specifically designed TGA methane tools will tell us a lot.” T
The TGO mission, which could distinguish between microbial and geological methane sources, will release its results next week.
“Checking the curiosity observations from the PFS tool certainly gives us a lot to think about,” said Patel. “Let's say it will make an interesting discussion in the community as we try to solve the observations of existing and new methane measurements on Mars.
“As always, Mars and the scientists who are studying are still having plenty of surprises up their sleeves.” T