Much more liquid water may lie beneath the south pole of Mars than scientists had thought — or there may be something going on down there that they don’t fully understand. It all has to do with interpreting the feedback from instruments.

The planetary scientists at Cal Tech have been certain that there was a deep salty lake under the South Pole. That was confirmed by radar data gathered by Europe’s Mars Express spacecraft. The lake appears to be about 12 miles (19 kilometers) wide, and it lies about 1 mile (1.6 km) beneath the dry, frigid surface, and filled with a salty liquid slurry that was mostly water.

The same core research team soon followed up on the find, using the same Mars Express instrument — Mars Advanced Radar for Subsurface and Ionospheric Sounding, or MARSIS for short — to study the subsurface in a wide area around the apparent lake. This work turned up evidence for three more underground lakes, each of them about 6 miles (10 km) wide.

Scientists are ever hopeful that water may mean life. I’m skeptical largely because of the Martian Historical Records (see picture above). Kidding aside, liquid water could suggest life. It’s a huge leap from “could suggest” to actual life.

A different team took another look at the radar data. Arizona State University doctoral student Aditya Khuller and MARSIS co-principal investigator Jeffrey Plaut, of NASA’s Jet Propulsion Laboratory (JPL) in Southern California, analyzed 44,000 observations MARSIS made of the Martian south polar region over 15 years. (MARSIS was built by the Italian Space Agency and JPL.)

The duo found dozens of radar reflections similar to the four that have been interpreted as buried lakes, over a wide range of horizontal and vertical distances. But many of the newfound signals were spotted relatively close to the surface, in places seemingly too cold to support liquid water — even the briny stuff hypothesized to exist in the Martian underground.

“We’re not certain whether these signals are liquid water or not, but they appear to be much more widespread than what the original paper found,” Plaut said in a statement. “Either liquid water is common beneath Mars’ south pole, or these signals are indicative of something else.”

It’s unclear what could keep so many relatively shallow lakes — if the newfound signals do indeed indicate lakes — from freezing over on frigid Mars. Volcanism is one possibility that researchers have raised, said Khuller, who conducted the new research while an intern at JPL.

The colored dots represent sites where bright radar reflections have been spotted by ESA’s Mars Express orbiter at Mars’ south polar cap. Such reflections have previously been interpreted as subsurface liquid water, but their prevalence and proximity to the surface suggests they may be something else.

The colored dots represent sites where bright radar reflections have been spotted by ESA’s Mars Express orbiter at Mars’ south polar cap. Such reflections have previously been interpreted as subsurface liquid water, but their prevalence and proximity to the surface suggest they may be something else. (Image credit: ESA/NASA/JPL-Caltech)

“However, we haven’t really seen any strong evidence for recent volcanism at the south pole, so it seems unlikely that volcanic activity would allow subsurface liquid water to be present throughout this region,” Khuller said in the same statement.

Neither Khuller nor Plaut can explain what exactly the newfound MARSIS reflections mean.

 

Only a rabbit and a duck stood between invasion and peaceful survival. The historical records show startling facts.

24 COMMENTS

  1. Water, either ‘fresh,’ mineral or salty, seems to exist everywhere. Planets, moons, asteroids, comets, weird interspace junk just passing through.

    But the rather peculiarly specific conditions to allow life as we know it to occur? Minimal range variations for heat, radiation, pressure, atmosphere, so on and so forth. It’s quite miraculous, knowing what we know now, that life exists at all here on Earth. Almost like some… supreme being shook up the results and Earth won the lottery.

    I doubt life of any sort still lives on or in Mars. Maybe some of Jupiter ‘s or Saturn’s moons. But not on Mars.

    Though finding water is a good thing for any future attempt at a long-term human settlement, even if only a research base or two or three.

    • I have no idea why we would do a manned landing on Mars except to prove that we can. Musk said that it was a one-way trip.

      It’s an exercise in hubris. A robotic research station is possible today. Maybe in 100 years, it would be useful. The Moon is a different matter. I think that a manned station on the Moon is possible in the next twenty years.

    • I’ve always thought that light has to penetrate an object and be affected in one way or another as opposed to bouncing off of one.

  2. Lee Strobel’s “The Case for the Creator” does an excellent job of outlining what it took for life to begin here on Earth, backing it up with scientific facts showing it wasn’t all happenstance, or Darwinian. Mars? Doubtful.

    • The thing about Darwinism that bugs me – from both “sides” – is the assumption that, for evolution to occur, it must needs do so in the absence of a Creator. It’s a process theory, nothing more, nothing less. Assuming it did occur, is occurring, does absolutely nothing to explain why it occurs, nor Who or what laid down the rules of physics and biochemistry that permit it, nor how rules of chance and circumstance just “happened” to allow life this once. Some One not only had a finger on the scales of probability, but made those scales in the first place.
      If Darwinism is false, I see a Creator’s hand in things. If Darwinism is true, I see a Creator’s hand designing and guiding it.
      Do i know how old the earth is, or how many days (as we understand the term) it took for the Seven Days of Creation? No, I was not there. But if hard proof (instead of theories built upon theories) emerged today that Creation was X or Y years old, at either extre of the spectrum, what we will find is that it was Man who misunderstood and misinterpreted the Bible and other evidence in favor of our own pet theories, not that the Bible or the evidence was lying or wrong.
      Remember, it was once considered contrary to the Church (if not outright heretical or blasphemous) to suggest our planet revolved around the sun, instead of the reverse. The Bible was NOT wrong in that case either; Man’s pride did not wish to admit the potential of error in interpretation.
      I have my own theories about the nature of Creation as a thinking layman, but they are mine and not ever to be confused with doctrine, dogma, or absolute truth.
      The Bible says “in the beginning, God created,” and that’s good enough for me. The how and when are lesser issues fun to discuss and boondoggle on, but they are of little importance to the message of the Bible.

      • I’ve sometimes wondered – Gen. 1:2 talks about the Spirit hovering over the face of the waters. It appears that humans think that the time hovering was measured in nanoseconds, but I see nothing that validates that assumption.

    • There is that TicTak facility on Mars inside Olympus Mons. I hate to mention that here, but, well, there you go. They’ve been harassing our jets long enough.

    • Here’s something that I find interesting.
      If life is rare in the universe, and I believe it is, Goldilocks principle and all, what are the odds that another race would develop, become space-faring at FTL and visit us surreptitiously?
      We should have been hard to notice, given where we live.
      Our presence (radio waves) is not announced FTL.

  3. I like the way this conversation went, but being an inherently boring guy, I went off and tried to figure out just what sort of radar MARSIS is. Most modern radars won’t see subsurface, so it figured it had to be low frequency, but I can’t find out what frequency it is.

    For the half century that space borne astronomy has existed, the pattern has been we put up a new instrument to observe in some part of the electromagnetic spectrum we’ve never observed in and we always find surprising things no one predicted. That gives me the gut feeling that MARSIS isn’t necessarily finding subsurface water and ice, it’s just finding something they weren’t expecting.

    Why the frequency matters is that radars only measure the signal strength of the radar signal’s reflections, and all radars will see things that are a quarter wavelength long better than things significantly longer or shorter than that. (Longer things also show up well if they’re a multiple of 1/4 wave long. ) This is why radar scattering chaff was small metal bits, sized for the frequency band the radar was using.

    MARSIS radar isn’t seeing “water”; it’s seeing something that reflects the way they think water reflects. Some sort of crystal? Some sort of metallic ore? It would be interesting to go digging where it thinks these underground lakes are to find out just what’s down there.

    • You’re 100% on point. There is something under the Martian south pole that reflects and it’s about a mile down. SiG knows a lot more than I do about this, but different bands of radar see the same things differently in the same way that things appear different if you’re looking at it with IR resolution rather than broad-spectrum sunlight.

      LIDAR might be in play here? Depending on the composition of the Martian soil. It will tell you that something is there, but not what that something is. Mars is a cold planet. And while it might be a liquid that incorporates water, it does not tell us what that liquid is (providing that it is a liquid).

      Punching down a mile on the Martian South Pole to take a sample isn’t a very easy thing to do.

      A lot of the ice on the Martian polar cap is CO2 – dry ice – mixed with a little water.

      • I never worked with Ground Penetrating Radar (we had enough trouble making it penetrate the sky…), but here’s an overview from the wiki:

        https://en.wikipedia.org/wiki/Ground-penetrating_radar

        And SiG is 100% correct. They’re going on the assumption that if it reflects like water, walks like water, and quacks like water, they’ve found water. All we have to go by are the reflected signals and 75 years of radar development.

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