Curiosity finds methane fluctuates seasonally in Gale Crater


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Seasonal methane on Mars

In its second significant science release yesterday (the first relating to the discovery of organics), the Curiosity science team revealed that they have found over almost three Martian years the amount of methane in the atmosphere appears to fluctuate seasonally. The graph on the right illustrates this change.

[The data] show methane rises from just above 0.2ppb in the northern hemisphere winter to a fraction over 0.6ppb in the summer. The team’s best explanation is that methane is seeping up from underground, perhaps from stored ices, and is then being released when surface soils are warmed.

The team cannot positively identify the origin of the methane, but the researchers think they can close down one particular mechanism for its production. This involves sunlight breaking up carbon-rich (organic) molecules that have fallen to the planet’s surface in meteorites.

The variation in ultraviolet light over the course of the seasons is not big enough to drive the scale of the change seen in the methane concentration, says Dr Webster. “We know the intensity of the Sun and this mechanism should produce only a 20% increase in methane during the summer, but we’re seeing it increase by a factor of three,” he explained.

The change could be caused by either a chemical or a biological process. At this time there is no way to determine which.

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18 comments

  • Max

    Good, some numbers I can work with.
    Where does the methane come from? The solar wind has higher concentrations than this. But the seasonal fluctuations would indicate that methane’s “love of ice” has stored it for long periods of time to be released seasonally when polar ice melts.
    Here on earth, methyl hydrate (methane in ice crystals under high-pressure) in ice on the ocean floor makes up more than twice the amount of carbon in all the coal on the planet.
    If methane was an indication of life, then Jupiter would be the largest source of life in the solar system.
    http://boletinsgm.igeolcu.unam.mx/bsgm/vols/epoca04/6703/%282%29Guzman.pdf
    At 0.2% of the atmosphere (2,000ppm) Jupiter has five times more methane than earth.
    Mars has 0.2 ppb to 0.6 “parts per billion”. Think about that. If you had 100 stacks of $100 bills 100 bills hIgh, that’s $1 million (or PPM). If you stack all that money in a large suitcase and add 100 stacks of suitcases 10 high, this would be $1 billion (ppb). The amount of methane they detected on Mars would be the equivalent of .20 to .60 cents out of a billion dollars.
    The margin of error is larger than the amounts detected.
    “We are seeing an increase by a factor of three” ??? (10x10x10)
    I think he misspoke, or I miss understand. That would put methane at .2 ppm. Nearly as high as earth with 1.8 ppm. (or the equivalent of $1.80 cents out of 1 million dollars)

    (as a side note, the abstract above says methane is eight times more efficient as a greenhouse gas than carbon dioxide. That makes earths retention of heat due to methane the equivalent of an additional 14.4 ppm of carbon dioxide. Carbon dioxide natural levels are near 400 ppm for a total of 414 ppm. If you know someone who is complaining of the evils of methane, do the math for them. Be nice, they end up feeling very foolish)

  • Lee S

    @ Max…. I’m sorry, it’s late on a Friday night…. I can’t follow your math… But when I walk the Scandinavian landscape… I see life EVERYWHERE …. Every rock, ( which are covered in frost and ice , down to Martian levels ) in the winter , spring to life with moss and whatever those grey and green plant/creatures are called that are so good at living on rocks…..
    When I walk through a north Scandinavian forest, I find it difficult to believe that life only exists on this planet…. Every nich is colonised here…. Every little slot is taken…
    ( lichen!!! That’s the name I was looking for!!)
    Seeing how life is so pervasive here on earth makes me think… Given the slightest chance…. It’s going to be elsewhere ….
    It’s just going to look for it…..

  • Lee S. You are absolutely correct about Earth. It is almost impossible to find almost any spot that isn’t teeming with life.

    Look however at the numerous pictures I have posted of Mars. There is literally no life in any pictures. None.

    Just because life is pervasive here on Earth is no guarantee it is pervasive elsewhere. It could be. I hope it is. But we have no evidence as yet that there is any, anywhere else but here.

  • Edward

    I’m not happy with the chart with respect to the article. The article says, “The roving robotic laboratory has seen wafts where the concentration has risen upwards of seven parts per billion (ppb)“, but that data point is not on the chart. The chart comes with a sinusoid-like line that helps us to visualize the point being made, but since it relates to season and contains one outlier (the first-year winter datum) and does not include an outlier datum mentioned in the article, I have to wonder whether there is a location factor that could be more important than the season factor. Could the line be fooling us into a false conclusion? Has Curiosity been passing methane vents? Because the 7 ppb datum was not included, I have to wonder whether there are other data points that were also not included? What other wafts (the article used the plural) were observed but not included?

    Max’s linked paper is interesting. It is a good find. Its conclusion (Final comments) results from evidence that life adds an enormous amount of methane into an atmosphere, but I am a little troubled about the paper’s intention.

    The paper states: “Today near to 50 % of CH4 global emissions are produced by human activity (mining, industry, farming, and ranching) causing an imbalance between their sources and sinks of 30 Tg year-1, approximately, contributing from 4 % to 9 % of greenhouse effect.” Table 1 and Table 2 give us CH4 sources and sinks. Although it is difficult to find the affect of human activity from most of the sources in Table 1, we can certainly see that 110 Tg of CH4 comes from human production of energy (extraction of fuel). 50% of the sources would be approximately 300 Tg.

    Since the net increase in CH4 is 30 Tg, and the vast majority of fuel extraction, mining, industry, and food production increase has happened during the past 100 years (population rose from 7 billion thus food production to match, and industrialization and energy use increased greatly worldwide), we can conclude that nature (the sinks) has adjusted to our imbalance by approximately 90% (30 Tg imbalance over 300 Tg production rate). In geologic terms, that is a rapid adaptation to human activity.

    It is curious how a paper describing methane in the solar system that “may be good evidence of life” is distracted from its expressed topic to investigate anthropogenic global warming. The greenhouse effect is only discussed for the case of Earth and is ignored for all other planets and moons. From the paper: “Because methane is also a greenhouse gas, release of even a small percentage of total deposits could have a serious effect on Earth’s atmosphere.” That is quite a statement, without evidence or reference, for a paper that is primarily concerned not about global warming or even greenhouse effects but about CH4 in the planets of the solar system as it relates to finding “good evidence life.

    Lee S,
    Max’s math is a little off when he says .20 to .60 cents out of a billion dollars. It should be .2 to .6 dollars out of a billion dollars (20 to 60 cents). Decimal points are a tricky devil, and were a good reason to go from slide rules to hand held electronic calculators.

    As for life being everywhere, first it has to start there or get there. If life ever evolved or otherwise survived on Mars, then I would expect that it is still there fighting to remain alive (just as the lichens and other plants/creatures in every niche in your frosty and icy region), hiding where we have yet to look.

    The real question(s) to answer are how easy or often it is for life to evolve on a planet or to migrate from one planet to another via asteroid knocked off the one to the other. If it is easy to form life or it otherwise forms often, then it should be common.

    SETI has studied the origins of life on Earth, especially as to how it may form elsewhere. A friend of mine from high school worked in a lab that studied the formation of chemicals that could form life, the primordial soup hypothesis. Then there is this hypothesis:
    https://www.youtube.com/watch?v=ofFhHcvasHA (3 minutes)

    There are plenty of hypotheses, but it will be hard to know the answers until we start finding extraterrestrial life, and we will know even more by examining it and comparing it with ours.

  • Max

    Yes lee, I also have been to the Arctic. It is easier to find life/food/water there than the desert of Arizona.
    If bacteria or some Lichen was able to make it to Mars, it would soon dominate the planet. Even though there is only .007 bars of pressure, it’s mostly carbon dioxide, plant food. It would not take long for lichen to cover every surface of Mars beginning the “oxygen cycle”. Dead lichen would give bacteria something to eat starting the “methane cycle”. The methane would oxidize and start the “water cycle”. And our dusty red mars would become a deeper shade of red as the oxygen is absorbed by the iron in the dirt and becomes rust.

    0.4ppb looks like this, 0.000,000,000,4
    It would have sounded like more if they said 4 thousand parts per trillion…

    If life as we know it is there, it could only survive underground in the lava tubes. Any oxygen and methane produced would need to be recycled in a closed system to maintain balance. Most of the collapsed tunnels that we have seen are sealed on the ends giving me faint hope.
    The stuff of sci-fi fantasies of ancient Martian civilizations is made of. As you said, “We will just have to go look for it.”

  • Cotour

    Timing is everything, in life.

    Might Mars have had at least bacterial life 1 or 2 billion years ago when it had an atmosphere and liquid water? (I assume there was liquid water based on the geology revealed by the rovers) And if so then 1 or 2 billion years have passed and it is just not apparent do to extreme periods of time and erosion.

    And to add to the problem the magnetic field was not strong enough to protect the planet from the harsh realities of space and the gravity also just not above critical mass to sustain an atmosphere over time.

    Mars seems a planet on the bubble to me, just not enough there there and more than likely if there was life of some basic sort it has been erased.

  • Localfluff

    They think that Mars lost its atmosphere already 4 billion years ago. They’ve calculated that little Mars had cooled enough by then to shut down the magnetic field. If Earth lost its atmosphere today and the oceans boiled off, we would still have plenty of subsurface life 4 billion years from now. The question is whether life ever originated on Mars or not, and that is irritatingly unknown. There’s no clue. No astronomical data. No biological theory. First life on Earth has certainly been exterminated long ago, so there might not be anything to observe. The oldest life known are bacterial and extremely advanced with a long random evolutionary history already. First life might as well have landed on Earth, there’s nothing that speaks against that.

  • wayne

    “New Mars Science Results”
    JPL
    June 7, 2018
    https://youtu.be/53kq635mpMs
    58:19

  • Cotour

    If Mars had no atmosphere up to 4 billion years ago, which is the aprox. ago of our solar system, I assume that that means that there is no liquid water available.

    Q: Where does all of the evidence of sedimentary rock layers come from?

    I would assume that if there is evidence of the molecular components of life and at some point liquid water which means a relatively stable atmosphere situation around long enough to create sedimentary rock deposits that at the minimum it is reasonable to assume that some minor form of life would be present. Bacterial at the minimum. And it would be very difficult to detect it at the level of investigation that we have available at the moment.

    What does earth teach? If the conditions for life are able to be generated and supported that it becomes a kind of infection and it is explosive in nature and spreads uncontrollably. The question remains, did that happen on Mars long enough to be detected?

  • wayne

    Cotour/Max/LocalFluff/Edward/Lee–
    (excuse if I’m co-mingling threads here, and I haven’t fully drank all my coffee…)

    –please address the level of Ultraviolet-C radiation on the Martian surface. UV-C is quite effective in killing biologic organism’s. The effects are cumulative and break down organism’s at the cellular level. (If our atmosphere didn’t filter out uv-c, we’d look like Mars.) The top few millimeter’s are totally sterile, although that does not preclude subterranean dwelling organism.)
    –“Perchlorates” in the Martian soil– contrary to Hollywood, potatoes aren’t going to grow in a toxic mix of perchlorates.
    –Ionizing radiation received at the surface.

    pivoting;

    “The Kilopower Project and Future of Nuclear Powered Space Travel”
    Patrick McClure
    May 16, 2018
    https://youtu.be/jjK-PZX2aZ0
    (48:50)

  • Localfluff

    @Cotour
    An argument against life on Mars is that life on Earth has totally transformed Earth as a planet. We are a living planet, one organism, one tree of life intimately grown together from and with our local environment. Life has completely changed our atmosphere, formed 90% of Earth’s minerals (which Mars lacks) and controls the cycling of elements through the crust. If you had nothing but a handful of sample of Earth from 10 km depth, you’d know there’s life here. Even if the sample is sterile, you’d know it from the minerals that life has formed.

    Maybe life originated independently on Mars but never evolved to cellular organisms before the surface got inhabitable. It is all very speculative, but it has been proposed that there might’ve been a non-cellular precursor to life as we know it on Earth, in the shape of bio-films. Like a thin biological coating of dust grains in a porous underground. Easy food for later life like bacteria. A speculation is that such primordial bio films might still survive so deep down that cellular life cannot stand the heat, but they can. I got that from the Deep Carbon Observatory team.

    I think that a thorough inventory of life on Earth should be done, and drill as deep down as doable to find its boundaries. There’s believed to exist 10^31 virus particles in Earth’s biosphere. A few years ago 400 of them had been genetically mapped. Today hardly more than a few orders of magnitude more, which still is nothing. Earth is as of yet the only data point the astrobiologists have. that doesn’t deter astronomers from doing statistics, except that WE are the living beings here and thus we are not an observation, but the observer. So statistics doesn’t apply.

  • Cotour

    All great points, very interesting.

    My base thinking is: If water is able to exist then life of some sort is able to exist. (Meaning that the temperature and gravity lends itself to the condition for water to be liquid and therefore life can germinate. Thats assuming that life as we know it requires water. No water, no life?)

    So in this discussion do we find that life is both more likely to exist at some level in the universe, and simultaneously very unlikely to exist in the universe?

    Like the question of existence of “God” and / or some “other” cause for the spark of life to exist other than the conditions we are discussing, we are usually left with more questions than answers the longer and harder we look.

  • wayne

    Localfluff–
    interesting stuff.

    time for some Jordan Peterson….
    {it’s nuanced…look beyond the Lobster…}

    “Stand Up Straight With Your Shoulders Back”
    Akira The Don x Jordan Peterson
    [“it has a good beat and you can dance to it”]
    https://youtu.be/dX0mcPfuCUQ
    (4:32)

    [we diverged from Lobsters, 350 million years ago, about the same time that Tree’s first appeared]

  • Localfluff

    Ridiculously nothing is know about the origin of life. Someone needs to come up with something, it is becoming embarrassing. But habitable spaces seem to be abundant. So human space flight just needs to put it there. To do the necessary planetary UNprotection. To spread life. And see what it grows up to become.

    When space aliens flew by Earth 4,000,000,000 years ago, one of the crew members made the joke that:
    “-Maybe 4 billion years from now a creature will have emerged from these rocks that blogs about us!”
    “- Thiihihiihuhuhuu”
    , as those aliens laughed. But here we are. And they won’t laugh when we cook them. Or if they still do, we’ll grind them. And if they still laugh, we’ll just eat them raw. Space is food for humans.

  • Cotour

    Again to my point about time.

    Our solar system exists only in the last 1/3rd of the existence of the universe, what went on over the previous 9 billion or so years before our sun was even a glimmer?

    100 or 200 billion stars within our / a galaxy, X’s the average number of planets that surround them, X’s possibly 100 billion to 1 trillion (???) galaxies. Hurts the brain, and we are the only life forms that have come about?

    “If time and distance is the measure of existence, then we are less then nothing”.

  • wayne

    Cotour/Localfuff–
    interesting points.

    I trend to believe, liquid water is a necessary, but not sufficient component unto itself.

    Ref: life being “able to exist,” doesn’t necessarily imply it will exist, but it certainly raises the odds, I would think.

    Q:
    Forgive my ignorance– are we 100% positive there is/was, no biologic life on the Moon? Has that been settled or what?

    totally tangential-
    Refresh my memory– who is the guy that thinks there was a nuclear war on Mars?

  • wayne

    The Formation of our Galaxy –
    Professor Joseph Silk
    Gresham College public lecture 2016
    https://youtu.be/w68bnqKdhps
    (1:03:21)

  • Localfluff

    @Cotour
    Astronomy has the luxury of being able to observe the past! The further away the further ago. The universe gets more dense the younger it is. Planets could’ve formed within the first 1 billion years. Actually, huge galaxies formed surprisingly early. Everyone is kind of waiting for JWST to throw some light on that.

    It isn’t even defined what life is. The attempted definitions define what we are. Life might be more general. There might be other interesting phenomena than life. Like our subjective consciousness, what causes that? Are there other kinds of subjective objects flying around out there? And see how human industry causes things that are hard to predict from non-human biology alone. The combinatorics of biology is larger than the visible universe. We know that there never has and never will exist for example a hemoglobin molecule anywhere in the visible universe. Unless it is physically related to our hemoglobin (which is closely related to chlorophyll btw, plants are our near and dear family). Time and matter are too small for it to occur twice. And there exists no mechanism to help it come into existence. Evolution only acts by selection of that which has happened to occur. It cannot help make something occur, that’s just random chance.

    So it seems to me that there will be great diversity out there. Anything is biologically possible maybe more than life (as our subjective consciousness or our industry). And it is impossible to calculate the possibilities of biology. It’s just a matter of what happened where. Most of the potential never happened. What we do know for sure is that nothing similar happened twice independently in unrelated biologies.

    @wayne
    You mean nuclear war on Mars Dr. Brandenburg? I don’t think he’s completely serious. He explains this one isotope on Mars with a nuclear detonation. But there are a hundred things that speak against that. I think he dramatizes it for fun.

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