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Finding “Tightens the Noose on the Possibility of Life” on Mars

Article written: 16 Feb , 2008
Updated: 26 Dec , 2015
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So far, the Mars Exploration Rover (MER) Mission has turned up very little evidence that there is, or was, life on the Red Planet. Even more bad news is on the way from data sent back from NASA rovers Opportunity and Spirit – it would seem that the planet was “too salty” for even the toughest organisms on Earth to survive. It would appear, from new results presented at the American Association for the Advancement of Science (AAAS) in Boston, that although Mars had abundant supplies of water in the past, its oceans would have been too acidic, with poisonous concentrations of minerals. Even when conditions were best on the surface, the very toughest microbes will have found it difficult…

The NASA MER mission has been a resounding success. Both Opportunity and Sprit have operated on Mars longer than any mission scientist would have dreamed. So far, both rovers have been trundling around on the planet for nearly four years, and have carried out some exciting science, analysing the Martian regolith and rocks, observing atmospherics and geology, not forgetting the spectacular panoramic photography… but they have yet to find any compelling evidence for life. Even after the excitement of Spirits big discovery back in Decemeber, the hunt for Martian life remains inconclusive.

Now, it seems, there’s another blow for life on Mars – it’s too salty. It’s been known for a long time that Mars once had large quantities of water, giving hope that life once thrived on the planet. But these new findings suggest the water may have been too rich in minerals, making it very difficult for life (as we know it) to survive.

It was really salty – in fact, it was salty enough that only a handful of known terrestrial organisms would have a ghost of a chance of surviving there when conditions were at their best.” – Dr Andrew Knoll, a biologist at Harvard University, speaking at the AAAS meeting.

Where Opportunity is right now - in Duck Bay (credit: NASA/JPL)
This news comes from Opportunity, currently working in Duck Bay (an alcove attached to Victoria Crater, pictured left) and these new results come from rock analysis in the region. Although this may be discouraging for scientists trying to find life on Mars, this is by no means the final straw. The Phoenix Mission is currently en-route to Mars and one of its mission objectives is to carry out advanced analysis for Martian life. Phoenix lands on May 25 of this year to hunt for life in the frozen North Pole. Also, the Mars Science Laboratory (MSL) is expected for launch in 2009 and will continue the hunt for organic compounds in the Martian regolith.

Source: BBC


31 Responses

  1. “only a handful of known terrestrial organisms would have a ghost of a chance of surviving there when conditions were at their best.”

    Isn’t that handful enough? If Earth were saltier, wouldn’t that handful have has a lot of progeny and diversity of descendants to capitalize on the otherwise uncointested biosphere?

  2. Owen says

    Maybe there are organisms that thrive in salty conditions. Just because organisms on earth wouldn’t survive doesn’t mean that the organisms of another world wouldn’t.

  3. K says

    So much for the 100% of probability that life would emerge when water is present.

  4. Adam says

    Considering they can’t recreate that “spark” of life. Who knows what life all needs to get started and, what combinations of various things could create it. I think they should really kick it up on some other planets/moons. It seems there are better places to look at the moment.

  5. David Madison, Sr. says

    At one time Mars had liquid water, and that water had dissolved salt and other minerals. In four billion years, the water evaporated. When water evaporates, the salts and minerals in it do not. As the volume of water decreases, the salt and mineral concentration increases. When the liquid water finally disappears entirely, the remaining evidence of that water will show extreme salt and mineral concentrations.

    Saying that the water on Mars was too salty and acidic to support life assumes that it was always that salty and acidic, a significant error in logic.

  6. J says

    And if our oceans, as salty as they are, dried up wouldn’t it leave behind layers of salt on the surface too? Could it be possible that the rover is taking samples from an area that was part of the ocean floor? We should see data concerning salinity from areas of higher as well as lower altitudes before we assume that the entire planet is too salty for life.

  7. Scott Maxwell says

    Well boys….its time to piss on the fire…call in the dogs…and go to sleep. Its over. Our childhood dreams and sci-fi thrillers led us down a road that goes nowhere. Mars is…and always has been hostile to life as we know it. All you dreamer die-hards can go on but the more rational of us know it is a done deal. Its time to move on to greener pastures.

  8. Johnny Blues says

    When presented with potentially disappointing scientific findings, it may be a good time to recall Eienstein’s “Greatest Blunder”. Works for me 😉

  9. marcellus says

    I think the guys that put out this report are the same ones that did the Mariner 4 flyby.

  10. Allan says

    Earth has salty oceans and salt flats, but we do NOT have salty rain or rivers. Is it not likely that early Mars was similar ??? What happens when the water evaporates…..??… the remaining salts and minerals become concentrated………PLEASE don’t give up on Mars just yet.

  11. Arnold says

    Just because the content is too salty for Earth’s organisms doesn’t mean it isn’t fit for any organisms whatsoever. Look at our prospect of Europa. They claim that there could be liquid water oceans in a place so cold, how could life possibly survive? How about the deep sea organisms of Earth, living under such extreme pressure and harsh conditions that no near surface organism could survive? Evolution makes everything possible. If Earth organisms were exposed to a saltier environment, history shows we would have adapted to deal with it. In order to fully understand this, I think humans need to broaden their view of life and how it can survive, and perhaps that organisms as we know are semi-unique to our conditions.

  12. This is not new news, the fact that the water on Mars was far from pure H2O. Indeed the identities of the salts disolved in it were established some years ago.

    However it is always good to have confirmation from another source.

  13. Mika Viljakainen says

    Actually this piece of news is quite encouraging for multitude of reasons.

    Firstly, it seems to indicate the scientists working on the field are both professional and honest enough to quell hype. This should be the key trait for all those referring themselves as scientists.

    Secondly, if the overall setting on Mars would have had been very similar to a that of early Earth, would the possible discovery of Martinian fossils or organisms be that interesting? Finding a similar or related set of extremophiles on Mars than what we have here on the Earth would not to be that groundbreaking, actually. (Read; contamination between the planets at some stage in the long history of our Solar system)

    At least it seems quite possible that chemical and biological evolution would have had to adapt entirely or at least somewhat different course on Mars than on the Earth.

    And that’s exiting!

  14. john says

    Since we have a sample of 1, for planets with life, let’s just wait and enjoy the fun of exploring.
    We keep finding the universe is stranger than we can ever imagine, so lets enjoy this adventure and leave the expectations to somebody else.

  15. Johnny Blues says

    Over again, we rebel from evidence that life/we are more unique than makes us comfortable, Pox on being alone in all….this.

    Oddly, that reaction I also share is based on what evidence I could gather on my neighbors house by remote. How startlingly different his household is from mine. Mars is just one house away…..reach further, expand the researh database.

    Or, conclude based on just your neighbors house.

  16. Carl Rollberg says

    Maybe you should compare findings with The Great Salt Flats here on Earth. I agree with people with the theory of water evaporation leaving minerals behind.

  17. Bruce Kitchen II says

    I have enjoyed the Mars experience but just as I have said for years, Mars is devoid of life. I have had serious doubts about Mars being able to support even the hardiest of microbes. It is now beginning to look more and more like we should turn our “life-quest” search to Europa, Titan, & (maybe) Enceladus. I have been a Europa drum banger for years and I am actively lobbying NASA, JAXA, & ESA to get the ball rolling for some Europa probes.

  18. giovanni says

    how can we be sure that extra terestial live doesnt exist on mars? i mean all our research for life on mars so far has always been compared to life on earth but lets faced mars is not earth.

  19. John Bingamon says

    OK, I’m guilty of just reading the post without trying to find and read the original paper, so I speak from ignorance — BUT:

    Regarding the comments that current salt would obviously be far more concentrated than in the past, and therefore the scientists are too pessimistic: DUH!

    Given that that’s a point so obvious that a high schooler would notice it, I cannot believe that the authors did not take that into account. It is unfortunate that the report above doesn’t give us more details, but I would be willing to bet that the original authors did one of the following: (a) based on current evidence, estimated the total salts/minerals that would have been dissolved in past, and the total water that would have been present, and derived an estimate for concentrations from that, or (b) used more subtle evidence from the nature and abundances of the minerals present today to estimate at what concentration they must have been before forming deposits.
    But in any case, I am sure they did NOT simply base it on CURRENT concentrations, when there is no appreciable water present.

  20. Chuck Lam says

    Whoa! Hold on! Mars water evaporated! Where did it go? Mars gravity is .38 that of earth. Certainly enough gravity to prevent water vapor from escaping to space contrary to some theories . Or am I missing something. Let’s not get excited now, it is possible that Mars 246 Lbs per cubic foot of dirt density just may be porous enough to have absorbed what-ever short-period water there was at one time on the surface. The water could still be on Mars, albeit underground. We need a probe on the surface of Mars that will do some serious water prospecting. Life on Mars? Why not?

  21. John Guhn says

    Life doesn’t always form and if it did it doesn’t always adapt to changing conditions. If that were always true dinosaurs would still be walking the Earth. If there is no life discovered at Mars North Pole, and by that time still no evidence from Opportunity and Spirit , then it’s probably time to start putting more of our focus on Europa and Titan. With 8 planets and their 165 moons (not counting Pluto and Eris and their combined 4 moons) we still have plenty of other places to look as well. But, since many of those planets and moons lie at extreme tempature ranges in our solar system and many of the “moons” are only 1-10 km in length I would say that Europa and Titan are our only hope after Mars before we need to concentrate on other solar systems in Milky Way.

  22. K says

    That’s nice. Since there’s no life, hasn’t been any life, won’t be any life, can we please colonize the dump and move forward now?

  23. John M. Kulick says

    When it rains, it is not salt water that comes down.

    Since there is evidence of streams and rivers on Mars it is logical to conclude that there would be areas with less than fatal amount of salts.

  24. Yael Dragwyla says

    A datum is not a statistic. Spirit and Opportunity have done yeoman service on Mars, but only in two very restricted locations. Concluding that life native to Mars is virtually impossible on the basis of two parochial data sets confuses the trees for the forest. That the two sampling sites are widely separated still doesn’t say much about the surface of Mars overall, or the possibility of life native to it. I’ll readily give you that we’re not ever going to meet Deja Thoris and her people on Mars, but life per se still hasn’t been ruled out globally. And as someone pointed out, when water evaporates, its salts and other evaporites don’t. What we’re seeing in the rovers’ findings won’t really have much meaning until placed in a context depending on a whole host of factors, having to do with everything in the environment of the areas in which the samples were gathered. People like to jump to sensational conclusions, but altogether too often the jump turns out to be premature — and somebody takes a fall. Let’s wait a while longer, and gather a great deal more, and more detailed, data from Mars, before we make any final decisions about the matter.

  25. Brian says

    It is very possible that life could exist on Mars. If the water is deep underground, any bacteria would likely be found alive there rather than on the surface.

    In response to John Guhn’s comment “and if it did it doesn’t always adapt to changing conditions. If that were always true dinosaurs would still be walking the Earth.” This would be true for natural and slowly changing contitions. However, being hit by a massive comet (or asteroid) does not count as either natural or slow. The climate radically shifted so fast that life on Earth couldn’t change fast enough, and most of the plants died. After that, most of the dinosaurs went with them.

  26. Pedro says

    OK!

    Life on Mars seems to be growing further and further away as a real probability. But, as yael say, how much of the surface have we analised?

    Yeah, sure. These last revelations are a hard blow on our hopes for finding life but it seems to me very, very, very premature to close the shop and give up on Mars.

    Moreover, would Mars be a disapointing planet if no Life was there to be found? If that so, why did we go to the moon? To search for the ‘old man’?

  27. alphonso richardson says

    Ho hum…. it may not be the end, but it’s looking increasingly doubtful if anyone’s gonna turn up at the party on the Red Planet, extremophiles or not.
    It’s been fun, some great science has been carried out, but, until more far-ranging missions can be done (if ever), I agree that it’s a done deal. Good on the scientists for admitting that they’ve done their best.

  28. Bruce Kitchen II says

    From a purely scientific point on ‘salt’ – the term is commonly used in chemical definition to mean – METAL. or metal rich. I think what the Steve S. is saying about Mars is that yes, water is likely in deep deposits. But the real problem is that we know that Mars is ‘rusty’ – VERY VERY metal heavy with large amounts of iron oxide and the likes. What this means is that carbon doesn’t stand up to mixing with salts (ie., metals) very easily. Yes, life may be there, but more likely it is not because it is just too mineral rich and full of iron.
    That being said, and being a scientist and engineer, I can say that there is always a window of opportunity for life – but to find it costs how much? If life is on Mars, where do we look and how much money and resources do we want to spend on sending a ba-zillion probes there? It’s a dart shoot-out as far as I’m concerned. Wait until astronauts go there. They will have a better idea of where to look. In the meantime, spend the money on Europa and Titan.

  29. Pete says

    The finding of MER, that the planet is too salty to sustain any life does not encompass the whole of Mars but a small portion. I wonder if soil tests of some parts of the Earth would reveal similar data. We have literally scratched the surface of our own planet and we do research on others with the same strategies. We have alot to learn and much more to discover before we could know what to look for.

  30. Cosselbray says

    So, extant life unlikely/absent on Mars, that removes one more excuse not to go there. We no longer have to “jump through hoops” to avoid contamination. Great news.

  31. Adam says

    we are too concerned about life on mars, how about we continue study on life on EARTH!?!? But what do I know, I’m just a 12-year-old kid with A.D.D.?(seriously) Plus, how do we know the martain organisms didn’t live on the salt? NEWS,”scientists”:just because you think it or say it, doesn’t make it true(or furthermore,logical) Well……I supose it doesn’t mater. If you’ve seen Doom(a movie about martain alien/demon/morphed humans, you probably want nothing to do with mars) So the butt of the story is,keep your mind open to ideas that may seem crazy…………it just might be the answer. See you explorers later. This has been a 12-year-old kid giving adults advice.

    Oh, yeah,umm A.D.D. stands for attention deffecet dissorder……… NOT: a dumb dumb.

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