Curiosity Found Evidence of An Ancient Freshwater Lake on Mars

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Shortly after NASA’s Curiosity rover landed on Mars in August 2012, the scientists guiding the device decided to make a temporary detour before heading to the mission’s ultimate destination, Mount Sharp. Last spring, they guided the six-wheeled machine towards Yellowknife Bay, a slight depression with intriguingly lighter-toned sedimentary rocks, and drilled its first two holes in Martian rock in order to collect samples.

Afterward, as Curiosity drove away from Yellowknife Bay, onboard equipment ground the rock samples to a fine dust and chemically analyzed their content in extreme detail to learn as much as possible about the site. Today, the results of that analysis were finally published in a series of articles in Science, and it’s safe to say that the scientists probably don’t regret making that brief detour. Yellowknife Bay, they discovered, was likely once home to a calm freshwater lake that lasted for tens of thousands of years, and theoretically had all the right ingredients to sustain microbial life.

“This is a huge positive step for the exploration of Mars,” said Sanjeev Gupta, an Earth scientist at Imperial College London and a member of the Curiosity team, in a press statement on the discovery. “It is exciting to think that billions of years ago, ancient microbial life may have existed in the lake’s calm waters, converting a rich array of elements into energy.”

Written By: Joseph Stromberg
continue to source article at blogs.smithsonianmag.com

11 COMMENTS

    • In reply to #1 by Jos Gibbons:

      Would tens of thousands of years be long enough for microbial life to evolve?

      Bacteria have a generation time of as little as 20 minutes, so tens of thousands of years would be plenty of time for new species to evolve. The more interesting question is whether conditions on Mars billions of years ago allowed new life forms to appear and become established, independently of the appearance of life on Earth. It is also entirely possible that life originated on only one planet and was transferred elsewhere in the solar system by meteoritic bombardment. We could all have Martian ancestors! We need to be careful to distinguish the origin of life, which is unknown, from its evolution, which is comparatively well understood.

  1. It’s funny how obsessed we are about finding evidence of life beyond Earth. We seem to think life enormously important, probably because we happen to have it, but a vanishingly small proportion of the universe appears to be contaminated with it and there is absolutely no evidence that life has ever played any role in the history or evolution of the universe. I suspect that life is probably quite common, partly because it appeared on Earth almost as soon as it was physically possible, and I am interested in the questions of its origin and evolution. But if and when we do discover it (or its remains) elsewhere, it will simply, for me, be a confirmation of a long-held and reasonably based suspicion. No doubt, though, it will generate huge passions in those for whom life on Earth, in particular, has to have a purpose.

    • In reply to #2 by Macropus:

      It’s funny how obsessed we are about finding evidence of life beyond Earth. We seem to think life enormously important, probably because we happen to have it, but a vanishingly small proportion of the universe appears to be contaminated with it and there is absolutely no evidence that life has ever…

      Thanks, a cheery post and one I can’t help but agree with. Would it be significant if there were bacteria elsewhere? What would it tell us? and if there was intelligent life out there (with or without basic antivirus software) what would it mean for us? Would we be equals or more likely pets, or turned into gladiators for the entertainment of our overlords with that damned music from Star Trek I can’t get our of my head playing on continuous loop?
      On the other hand as someone far wiser and cheekier than me once sang:

      So remember, when you’re feeling very small and insecure,

      How amazingly unlikely is your birth,

      And pray that there’s intelligent life somewhere up in space,

      ‘Cause there’s bugger all down here on Earth!’

      He also said ‘A nod’s as good as a wink to a blind bat.’ So, maximum respect!

  2. I’d be gobsmacked if life didn’t arise on Mars, providing there was sufficient water for long enough. Many scientists believe that life arose around hydrothermal vents, and Mars certainly had volcanism. There would have been no ozone layer on Earth or Mars at that time, so underwater or underground would seem to be favourite. And if life did evolve there, it’s possible it still clings on beneath the surface.

    • In reply to #5 by ianw16:

      I’d be gobsmacked if life didn’t arise on Mars…

      Why be gobsmacked? There’s simply no future in it. It’s entirely possible that life didn’t arise on Mars. We know so little at this stage about the conditions on Mars over the past few billion years that we should be all ears, and open to the evidence. You’re right about the possibilities of subterranean life on Mars, but they remain purely speculative at this stage.

  3. Strange that a “scientist” suggested that microbes might have been “converting a rich array of elements into energy”. Was this a fission reaction or fusion? If neither, then how exactly?

    • In reply to #8 by exyfeplin:

      Strange that a “scientist” suggested that microbes might have been “converting a rich array of elements into energy”. Was this a fission reaction or fusion? If neither, then how exactly?

      Good question. Matter is not converted to energy in chemical reactions – only in nuclear reactions, as you say – and we have not yet evolved nuclear reactors! It’s fascinating to speculate on what a nuclear-powered animal or plant might look like.

      The energy obtained from food and used for living processes (heat generation, muscle contraction, nerve function etc.) is chemical bond energy, derived from the breaking and formation of chemical bonds (mostly covalent bonds) during chemical changes. To be charitable to the “Earth scientist”, he might have meant to say “converting a rich array of elements into organic compounds”. But even then, organic compounds are mostly synthesised from inorganic compounds, rather than elements.

      • In reply to #10 by Macropus:

        In reply to #8 by exyfeplin:

        Strange that a “scientist” suggested that microbes might have been “converting a rich array of elements into energy”. Was this a fission reaction or fusion? If neither, then how exactly?

        Good question. Matter is not converted to energy in chemical reactions – only i…

        To be fairer to the scientists it is the conversion of the elements into and between compounds that accesses the energy. Apologies though to exyfeplin if I trod on his jest…

  4. In reply to #8 by exyfeplin:

    Strange that a “scientist” suggested that microbes might have been “converting a rich array of elements into energy”. Was this a fission reaction or fusion? If neither, then how exactly?

    Chemistry has exothermic reactions producing heat (exo- means reactions give heat out). Organic chemistry in living things has the same sort of processes. You eat food to extract the calories to stay warm. (The process, though the same, is described in biology as endothermic, relating the process to the organism, hence endo- or heated from within.)

    More importantly energy is often defined as the ability to do work (and conversely work is the use of energy). Chemical energy got from the elements can do lots of different kinds of work not just that mediated by heat production. Chemical reactions always involves the transaction of energy. Muscle action consumes this chemical energy producing directed kinetic energy. Thinking also consumes chemical energy to direct those muscles.. both processes are not a 100% efficient and heat is the most notable byproduct.

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