Catch up on stories from the past week (and beyond) at the Slashdot story archive

 


Forgot your password?
Close
typodupeerror
×
Mars NASA

NASA Confirms Thousands of Massive, Ancient Volcanic Eruptions On Mars (nasa.gov) 49

Posted by BeauHD from the land-before-time dept.
Scientists found evidence that a region of northern Mars called Arabia Terra experienced thousands of "super eruptions," the biggest volcanic eruptions known, over a 500-million-year period. NASA reports the findings in a post: Some volcanoes can produce eruptions so powerful they release oceans of dust and toxic gases into the air, blocking out sunlight and changing a planet's climate for decades. By studying the topography and mineral composition of a portion of the Arabia Terra region in northern Mars, scientists recently found evidence for thousands of such eruptions, or "super eruptions," which are the most violent volcanic explosions known. Spewing water vapor, carbon dioxide, and sulfur dioxide into the air, these explosions tore through the Martian surface over a 500-million-year period about 4 billion years ago. Scientists reported this estimate in a paper published in the journal Geophysical Research Letters in July 2021. "Each one of these eruptions would have had a significant climate impact -- maybe the released gas made the atmosphere thicker or blocked the Sun and made the atmosphere colder," said Patrick Whelley, a geologist at NASA's Goddard Space Flight Center in Greenbelt, Maryland, who led the Arabia Terra analysis. "Modelers of the Martian climate will have some work to do to try to understand the impact of the volcanoes."
[...]
One remaining question is how a planet can have only one type of volcano littering a region. On Earth volcanoes capable of super eruptions -- the most recent erupted 76,000 years ago in Sumatra, Indonesia -- are dispersed around the globe and exist in the same areas as other volcano types. Mars, too, has many other types of volcanoes, including the biggest volcano in the solar system called Olympus Mons. Olympus Mons is 100 times larger by volume than Earth's largest volcano of Mauna Loa in Hawaii, and is known as a "shield volcano," which drains lava down a gently sloping mountain. Arabia Terra so far has the only evidence of explosive volcanoes on Mars. It's possible that super-eruptive volcanoes were concentrated in regions on Earth but have been eroded physically and chemically or moved around the globe as continents shifted due to plate tectonics. These types of explosive volcanoes also could exist in regions of Jupiter's moon Io or could have been clustered on Venus. Whatever the case may be, Richardson hopes Arabia Terra will teach scientists something new about geological processes that help shape planets and moons.
This discussion has been archived. No new comments can be posted.

NASA Confirms Thousands of Massive, Ancient Volcanic Eruptions On Mars More

NASA Confirms Thousands of Massive, Ancient Volcanic Eruptions On Mars

Comments Filter:
  • The Martians moved here

  • Oceans of poor scientific reporting (Score:3)

    by Rosco P. Coltrane ( 209368 ) on Thursday September 16, 2021 @06:04AM (#61800723)

    oceans of dust and toxic gases into the air

    First of all, aren't oceans of stuff in the air called "clouds"? Or is it officially reserved to refer to shitty 21st century-style mainframe computing now?

    Secondly, what air? Air is the name of the particular cocktail of gasses present in Earth's atmosphere if I'm not mistaken.

    • Air is the name of the particular cocktail of gasses present in Earth's atmosphere if I'm not mistaken.

      You aren't wrong, but there's no particular reason why other atmospheres couldn't be called air, and since atmosphere is a big word I predict that the masses will go ahead and do that if they are thinking about other planets. And they are doing that now due to these billionaires' space programs.

    • Ocean, lake, pond, river, stream, etc all describe volume and motion of water. Clouds and cloudy is more ambiguous. Notice we call it a jet stream. This usage helps avoid ambiguity and as noted in the previous example is already common vernacular.

      More so your second point misses that it's a phrase, "into the air" as meaning "into the atmosphere". The general mixture you note as "air" is literally defined by this process. We can say there is methane in the air because cow farts put it into the air. Thus any

    • "Air" is, indeed, a poorly defined term. Which is why it is rarely used in the technical literature.

      Planetary science concerns itself with those materails of fixed shape and volume ("solids"), those of fixed volume and changeable shape ("liquids"), and those of variable shape and volume ("gases", comprising an "atmosphere"). Individual materials can move from one state to another, typically absorbing or releasing considerable amounts of heat energy in the process - what we call "snow melt" or "cloud format

    • > aren't oceans of stuff in the air called "clouds"

      It's called a rhetorical device. They're quite common amongst the more educated of them book-readery types.

  • Absence of horizontal movement (Score:5, Interesting)

    by RockDoctor ( 15477 ) on Thursday September 16, 2021 @07:25AM (#61800805) Journal
    My take is that they are commenting on the apparent absence of horizontal movements on the surface of Mars, compared to Earth. On Earth, a long-lived volcanic province would have spread out laterally, and probably resulted in a split in the plate on which it formed. On Mars, that doesn't seem to have happened, and the volcanic centre just sat in one place and built up.

    So the fundamental question is, why does Earth have plate tectonics, and Mars have something different - to which we probably already have the answer : size. Earth is still radiating about equal amounts of it's "primordial" heat of formation (energy from impacting dust, asteroids, Mars-sized bodies) and "radiogenic" heat production (from nuclear decay of elements in the body of the Earth) ; Mars, OTOH, having about 1/10 of the mass of Earth, has long since radiated most of it's primordial heat (initially, about 1/10th of Earth's inventory) and is now mostly radiating it's radiogenic heat (again, about 1/10th of Earth's production rate). That reduced Martian heat flow is almost certainly why Mars has different tectonics to Earth, though connecting those two dots remains an incomplete task (to which this work is a contribution).

    The heat flow experiment (HP^3 [wikipedia.org]) on NASA's recent InSight [wikipedia.org] lander was intended to address this question precisely, but the probe's "self-drilling" feature doesn't seem to be working for reasons under investigation and experimentation.

    Other planetary scientists are trying to understand Venus' geological history and it's style of tectonics - in which they are hampered considerably by the thick atmosphere. At 81% of the Earth's mass, it's evolution may suggest how finely balanced the conditions necessary for plate tectonics are. Of course, we do not know if a planet with plate tectonics is a necessary condition for the evolution of life.

    • Re: (Score:2)

      by Viol8 ( 599362 )

      "to which we probably already have the answer : size."

      I remember reading somewhere that liquid water was also important as it helped lubricate things somewhat. Whether thats the case or not I don't know but it would certainly explain why venus doesn't have any apparent tectonics despite its size.

      • It is certainly hypothesised. That is a very different thing from being either a consensus opinion or "proven" - to whatever standard you want.

        There is indeed a debate over how much the subduction of wet sediment leads to metasomatism of the overlying mantle wedge (getting water into the mineral structure, at fractions of a percent by mass) ; and then to how well that material is mixed with the rest of the mantle - diamond inclusion provincialism suggests that the mantle is not "well mixed".

        Plenty of deba

      • Re: (Score:2)

        by cusco ( 717999 )

        It lubricates plates to some extent, but more important is that it is incorporated into rocks that are pushed under other crust. These hydrated rocks are lighter and have a lower melting point, blobs of low viscosity hydrated melt (I think that's the word) circulate around through the upper mantle on the convection currents and help impart motion to the plates above them.

        *Disclaimer* - My last geology class was over 30 years ago, so that may not be the current understanding.

        • Sometimes distinct "blobs" of hydrous melt can be seen in the seismic, but more often it is probably "chimneys" of ascending fluids - which can be seen as streaks of alteration where lower crust materials get exhumed (50, 100, 150km, vertically) to the surface. When they get into the lower crust, the fluids spread out, interact with the surrounding material (granulite grade meta-granites from the upper crust, similar grade meta-dunites and meta-lherzolites from former-mantle underplated onto the bottom of t
    • Perhaps aside from loss of heat, smaller size also may have contributed to early loss of water (lower escape velocity for Jeans escape), and we already know how lithospheric water is important for tectonic processes.
      • That could be a contributing factor too.

        We don't really know how well mixed the Earth's initial complement of water was in the more solid, less volatile parts of the mixture. Certainly the consensus is that the Earth was born "dry" and had water added (in a "late heavy bombardment", or earlier, or later, if such a thing ever happened) later ; but that is a consensus, and not a strongly held opinion.

        It's the old problem of having a sample of 1, and trying to generalise from that. We need a bigger sample, c

    • we do not know if a planet with plate tectonics is a necessary condition for the evolution of life.

      There's good reasons to believe rotation period or tidal effects have ramifications for the production of life, but not so much plate tectonics since they operate so slowly.

      • Plate tectonics on the Earth meant the super continent Pangea was broken up which had huge ramifications for life in terms of migration and isolation alone. Also weather is affected by indirectly by tectonic movement. [youtu.be]
        • Pangaea was a johnny-come-lately. There were at least two, and probably three preceding assemblages of most of the cratons ("continent cores") and marginal microplates during the existence of metazoan life on Earth.

          Yes, continental drifting could have dealt, terminally, with some groups of terrestrial lifeforms. Except if something went back into the seas, in the way that possibly some groups of insects have done, some crustaceans, the turtles, whatever branch of the "reptiles" produced the ichthyosaurs,

      • There's good reasons to believe

        Yes, there are.

        But that's not proof. At best, it's a guide to further investigation. If you're using it as a guide, you've got to remember that it may be a misleading guide.

        In the period that life was developing on Earth, the rotation period was probably approaching half that of today while the tidal forces were (order of) 8 times as high as today (the Moon being considerably closer, and receding at a variable, tectonically modified, rate). So ... what rotation rate and tida

      • There's good reason to hypothesize. I wouldn't say there's good reason to believe.
        It's a solid hypothesis. It's perfectly plausible, and it's easy to demonstrate ways in which it could have helped.

        At the same time, it's equally as easy to imagine that life didn't need it one bit.
        • It's a reasonable hypothesis to investigate when we have a second sample of "life" to investigate.

          Sorry, I'll rephrase that. When we investigate a second locale in which life developed.

          Finding a different, non-overlapping tree of life on Earth - say (and this is just a vaguely plausible word salad, not a serious proposition) one based on 28 amino acids controlled by a triple-stranded PNA genetics system, found in the interstices of rocks 5km below the surface (~0.5GPa) and deeper. Finding such a "second l

          • Agreed entirely. People should take care to look at life as we know it and not fall prey to letting our local conditions poison the base theories.
            That's not to say that "rotation period or tidal effects have ramifications for the production of life, but not so much plate tectonics since they operate so slowly." might not be true. Just that using the word believe is extreme. It's pure conjecture at this point, and we're attempting to infer something based on really bad information - until science agrees on
            • We have a sample of ONE datum. From that we can ONLY estimate the mean for {any parameter}, and our estimates for the variance (skewness, kurtosis) of {any parameter} is derived (through many steps) from our data on planetary (size, insolation, lifetime).

              Finding a second instance of life will narrow (or widen) our estimates considerably because (1/(n-1)) is not undefined for n<>1.

              • I'm beginning to wonder if you're not confusing science with statistics.

                Only in the most abstract sense can we say we have "one datum"
                And ultimately, even if we did only have 1 datum, that does not preclude coming to a definitive answer about the needs of life.
                Science allowed derivation without needing statistical data.

                I'm not saying this has happened- as I said, we've yet to find some kind of "cosmological principle" for life, as our understanding of it is still pretty infantile.
                Einstein did not nee
                • I'm not not putting a statistical cart before a horse of data. We still only have one example of life developing from non-life - on Earth, under conditions we (I use the geologist's "we") are stull arguing about and are far from certain of. We do not have, a priori, any significant constraints on what happened.

                  that does not preclude coming to a definitive answer about the needs of life.

                  You seem to think that we know more than we do. Just by chance, I happened to be downloading a bunch of podcasts on science

                  • I'm not not putting a statistical cart before a horse of data. We still only have one example of life developing from non-life - on Earth, under conditions we (I use the geologist's "we") are stull arguing about and are far from certain of. We do not have, a priori, any significant constraints on what happened.

                    This goes back to what I said. I think you're mixing statistics and science.
                    Of course we don't have, a priori, any significant constraints on what happened.
                    But we do have constraints, and those constraints can be filled by scientific knowledge. They don't need statistical data.

                    You seem to think that we know more than we do. Just by chance, I happened to be downloading a bunch of podcasts on science themes earlier today ("The Infinite Monkey Cage" - you may know of it), which included a 3/4 hour programme devoted to the question of "What is life". I think that was a few years ago ; perhaps a decade. But to the best of my knowledge, there is still no agreed definition of what "life" is. (If you know of a generally agreed definition, do provide a citation. I'll be astonished to hear of it's existence.) In that condition, being confident about the needs of a phenomenon we still don't have a definition for seems a touch premature. We probably have more understanding of the phenomenon of ball lightning than we do of "life".

                    Nonsense. I said flat out that we don't know much about life. But life is a science like any other, the rules for it can be derived without rote statistical collection.

                    Poor example. Einstein didn't (from his published diaries and papers) didn't start seriously thinking about "relativity" until about 1899, while Lorentz proposed his length-contraction concept in about 1890 - to explain the negative outcome of the Michelson-Morley experiment of the previous decade. That Einstein's approach (taking Maxwell seriously) produced the same contraction/ time dilation factor was considered a very suggestive point - the "unreasonable effectiveness of mathematics", as Einstein later wrote.

                    Perfect example.
                    As I said, time dilation.
                    It was Einstein who p

Slashdot Top Deals

Saliva causes cancer, but only if swallowed in small amounts over a long period of time. -- George Carlin

Close