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But now NASA thinks it may have found a solution.
But now NASA thinks it may have found a solution.
Because it needs a lot of power, TLS operates mostly at night when no other Curiosity instruments are working, says NASA. That’s when the Martian atmosphere is calm at night and methane seeping from the ground builds up near the surface where Curiosity can detect it, the agency notes.
ESA’S Trace Gas Orbiter, on the other hand, requires sunlight to pinpoint methane about 3 miles above the surface.
So, NASA made specific measurements using the TLS instrument during daytime and also confirmed a non-detection of the methane gas. Webster and colleagues detailed their results this week in The Astronomy and Astrophysics Journal.
Over the past two decades, the authors point out, Mars measurements from a wide variety of platforms (ground-based telescopes, orbiters, and rover) have reported methane values from zero to some 45 parts per billion by volume.
We report that the very low methane levels measured at night —- possibly from a subsurface seep —- are dissipated and dispersed when the sun comes up, Paul Mahaffy, the principal investigator of SAM, who’s based at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, told me. Our daytime measurements also give a null detection just like those from ESA’s orbiting TGO spacecraft, he says.
As for the methane measured in Gale Crater, the site which Curiosity has been exploring for nearly the past decade?
“With no evidence for methane production by the rover itself, we propose that the source is one of planetary micro-seepage,” the authors write.
Methane seepage from Gale Crater might possibly be from present or past microbial life of the variety that produces methane (methanogens) on Earth, says Mahaffy. But he says it’s equally plausible that this methane could be from past subsurface abiotic water rock interactions that also produced methane. สล็อตทดลองเล่นฟรี
If the methane we measure comes from a methane seep in Gale Crater, Mahaffy expects that this would also be happening in many places on Mars since, there are many similar deep craters on Mars.
Methane is a stable molecule that is expected to last on Mars for about 300 years before getting torn apart by solar radiation, says NASA. The agency notes that experiments are underway to test whether very low-level electric discharges induced by dust in the Martian atmosphere could destroy methane, or whether abundant oxygen at the Martian surface quickly destroys methane before it can reach the upper atmosphere.
Since we have seen occasional large spikes of methane orders of magnitude more intense than most of our measurements, I would encourage our European colleagues to just keep looking out for this signal as they orbit Mars, says Mahaffy. Methane release from the subsurface may be episodic and a sudden big burp may enable a TGO detection of this transient signal, he says.
Such methane detections are too important to do otherwise since most of the methane in Earth’s atmosphere originates from microbial activity.
Because it needs a lot of power, TLS operates mostly at night when no other Curiosity instruments are working, says NASA. That’s when the Martian atmosphere is calm at night and methane seeping from the ground builds up near the surface where Curiosity can detect it, the agency notes.
ESA’S Trace Gas Orbiter, on the other hand, requires sunlight to pinpoint methane about 3 miles above the surface.
So, NASA made specific measurements using the TLS instrument during daytime and also confirmed a non-detection of the methane gas. Webster and colleagues detailed their results this week in The Astronomy and Astrophysics Journal.
Over the past two decades, the authors point out, Mars measurements from a wide variety of platforms (ground-based telescopes, orbiters, and rover) have reported methane values from zero to some 45 parts per billion by volume.
We report that the very low methane levels measured at night —- possibly from a subsurface seep —- are dissipated and dispersed when the sun comes up, Paul Mahaffy, the principal investigator of SAM, who’s based at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, told me. Our daytime measurements also give a null detection just like those from ESA’s orbiting TGO spacecraft, he says.
As for the methane measured in Gale Crater, the site which Curiosity has been exploring for nearly the past decade?
“With no evidence for methane production by the rover itself, we propose that the source is one of planetary micro-seepage,” the authors write.
Methane seepage from Gale Crater might possibly be from present or past microbial life of the variety that produces methane (methanogens) on Earth, says Mahaffy. But he says it’s equally plausible that this methane could be from past subsurface abiotic water rock interactions that also produced methane. สล็อตทดลองเล่นฟรี
If the methane we measure comes from a methane seep in Gale Crater, Mahaffy expects that this would also be happening in many places on Mars since, there are many similar deep craters on Mars.
Methane is a stable molecule that is expected to last on Mars for about 300 years before getting torn apart by solar radiation, says NASA. The agency notes that experiments are underway to test whether very low-level electric discharges induced by dust in the Martian atmosphere could destroy methane, or whether abundant oxygen at the Martian surface quickly destroys methane before it can reach the upper atmosphere.
Since we have seen occasional large spikes of methane orders of magnitude more intense than most of our measurements, I would encourage our European colleagues to just keep looking out for this signal as they orbit Mars, says Mahaffy. Methane release from the subsurface may be episodic and a sudden big burp may enable a TGO detection of this transient signal, he says.
Such methane detections are too important to do otherwise since most of the methane in Earth’s atmosphere originates from microbial activity.