Since 2012, NASA’s Curiosity rover has repeatedly detected methane on Mars, particularly close to its touchdown web site contained in the 96-mile-wide (154 kilometers) Gale Crater.
However that Mars methane is behaving erratically. It solely seems at evening, it fluctuates seasonally and it spikes unexpectedly to ranges 40 occasions greater than normal. To make issues extra puzzling, the fuel is not current in considerable quantities excessive within the Martian ambiance, and it hasn’t been detected close to the floor in different Pink Planet locales. So what is going on on at Gale Crater?
A gaggle of NASA researchers led by planetary scientist Alexander Pavlov might now have not less than a partial reply. The crew suggests the Mars methane is trapped beneath a crust of solidified salt throughout the regolith at Gale. Heat daytime temperatures might weaken the crust, permitting methane to slide out at evening. And the load of a heavy rover driving over the crust might crack the crust, too, permitting methane to burst out in a concentrated puff. (Sure, it is akin to burping a child.)
Associated: NASA’s Mars rover Curiosity: The last word information
The researchers examined their speculation right here on Earth, utilizing a simulated Martian regolith; a salt known as perchlorate, which exists extensively on Mars; and neon as an analog for methane. Their exams, carried out inside a Mars simulation chamber at NASA’s Goddard House Flight Heart in Maryland, confirmed {that a} salt crust might kind beneath sure circumstances, trapping methane beneath it.
Whereas a layer of solidified salt may clarify the irregular habits of Martian methane, scientists nonetheless do not know why methane even exists on Mars within the first place. On Earth, methane is primarily produced by residing organisms — however we nonetheless have not discovered indicators of life on Mars.
And, to be clear, methane is just not a surefire signal of life; the fuel might be produced by geological processes as nicely.
“It’s a narrative with plenty of plot twists,” Ashwin Vasavada, Curiosity’s venture scientist at NASA’s Jet Propulsion Laboratory in Southern California, stated in a assertion. “A number of the methane work should be left to future floor spacecraft which can be extra centered on answering these particular questions.”
A paper on the crew’s analysis was printed on March 9, 2024, within the Journal of Geophysical Analysis.
