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Latest (brief) report on this question
research now suggests that Martian dust devils and storms produce oxidants that would render the planet's surface uninhabitable for life as it exists on Earth.
"As a consequence, any nascent life (microorganisms, for example) or even prebiotic molecules would find if hard to get a foothold on the surface of Mars, as the organic material would be scavenged efficiently by the surface oxidants"
Presence of life below the surface of Mars now or in the past is not ruled out by this research.
--similar article headline, from spaceflightnow.com:
Peroxide snow on Mars may make planet inhospitable
The planet-wide dust storms that periodically cloak Mars in a mantle of red may be generating a snow of corrosive chemicals, including hydrogen peroxide, that would be toxic to life, according to two new studies.
We all know [i]those[/i] Venusians: Doing their hair in shock waves, smoking electrical coronas, wearing Van Allen belts and resting their tiny elbows on a Geiger counter...
--John Sladek (The New Apocrypha)
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So you bring your own support.
You build inside of the planet .
SRAM
[b]JESUS IS GOD[/b]
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There are a few places on Earth where life is practically non-existent on the surface. One is probably the Atacamba (sic) Desert in Chile. Even there, you could dig down and probably hunt up a few microbes.
Rovers have a very slim chance of actually discovering life on Mars, since they only cover a limited area and can't really go underground.
There is very likely some life remaining on the Red Planet, but it's going to be underground. Two places come to mind:
1) Water occasionally wells to the surface on Mars. NASA pictures show it. Recent upwellings, not ancient ones. Look below the source of the upwellings.
2) Below the surface in caves where water still remains.
One general principle about 'life' in any form: If it ever existed, it is difficult to eliminate completely and totally. Assuming there was once life on Mars, to say that conditions have completely eliminated all remaining life is very unlikely. Life in itself is extremely adaptable, once it gains a foothold, and likely impossible to totally eradicate.
One way to look at it is this:
Imagine for a moment that tomorrow morning conditions on Earth changed to the exact conditions on Mars today. Of course...this would be the immediate end to civilization. However, in a hundred years, could you say with any certainty that ALL life, right down to the last microbe, would be destroyed? It is much more likely that SOME limited forms of life would somehow survive. This could be the case on Mars, since it is apparent that conditions favoring life were somewhat more favorable in the past. 8)
Don't give up reaching for the stars...
just build yourself a bigger ladder.
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<<One general principle about 'life' in any form: If it ever existed, it is difficult to eliminate completely and totally. Assuming there was once life on Mars, to say that conditions have completely eliminated all remaining life is very unlikely. Life in itself is extremely adaptable, once it gains a foothold, and likely impossible to totally eradicate. >>
Yes, but that doesn't get us anywhere. Microbial life is probably ubiquitous in the galaxy. the problem is how to get multi-celled life and then plant and animal life--that is the extremely difficult process that probably never got started on Mars.
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Here on Earth it seemed to be at the equator where it was warm and allowed for quick changes.
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<<One general principle about 'life' in any form: If it ever existed, it is difficult to eliminate completely and totally. Assuming there was once life on Mars, to say that conditions have completely eliminated all remaining life is very unlikely. Life in itself is extremely adaptable, once it gains a foothold, and likely impossible to totally eradicate. >>
Yes, but that doesn't get us anywhere. Microbial life is probably ubiquitous in the galaxy. the problem is how to get multi-celled life and then plant and animal life--that is the extremely difficult process that probably never got started on Mars.
But ... isn't the point of all this the determination that life of any sort is present off-Earth? To say that "microbial life is probably ubiquitous in the galaxy," and then go on to say that "multi-celled life and then plant and animal life ... probably never got started on Mars" draws conclusions we probably shouldn't at least yet, eh?
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This post is not to say that there is, or was, life on Mars, but merely to comment on evolution. The fact is, life forms are now demonstrated to evolve much more quickly than anyone had ever thought. Indeed, Anole lizards on some small Bahamian cays showed impressive evolutianary trends in six months. To me, this is remarkable, and opens the possibility of rapid evolution on Mars. After all, if here, why not there?
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http://www.livescience.com/animalworld/ … _legs.html
In a reptilian version of "Survivor," lizards with longer legs ultimately get booted from islands by their short-legged opponents.
Countering the widespread view of evolution as an eon-long process, evolutionary biologists discovered that when island lizards were exposed to a new predator, natural selection occurred in a six-month period, first favoring longer and then shorter hind legs.
The findings are detailed in the Nov. 17 issue of the journal Science.
Brown anolis (Anolis sagrei) lizards spend much of their time on the ground. But as previous studies have shown, when a ground-dwelling, predatory lizard is introduced, the anoles scamper up trees. They switch to an arboreal lifestyle to escape being eaten.
Anoles’ long legs make them fast runners, giving them an advantage in a ground-based setting where not much balance is necessary.
Researchers led by Jonathan Losos of Harvard University studied brown anole populations on 12 small islands in the Bahamas. They introduced a larger, predatory lizard (Leiocephalus carinatus) to six of the islands, while keeping six other control islands predator-free.
The scientists counted, marked and measured lizards at the beginning of the study, after six months, and again after 12 months. After six months, the anole populations dropped by half or more on islands with predators. On predator islands, the anole survivors had longer legs than non-survivors, a result the scientists suggest is due to longer-legged lizards being faster runners and better able to elude capture by predators.
Tables turned, however, during the next six months. The surviving anoles became increasingly arboreal, spending much of their time in treetops. At the end of the six-month stint, measurements showed surviving anoles had shorter legs compared with non-survivors. There was no significant difference in leg length between surviving and non-surviving anoles on control islands.
Shorter limbs are better suited for navigating narrow tree branches, which the scientists figure helped the lizards evade becoming dinner.
The researchers think that, over a longer period of time, the anoles in the presence of a predator would evolve much shorter limbs.
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Granted, this is hardly proof that life ever existed on Mars, nor that life is there now. Even so, since recent research indicates that the warm period of Mars was much longer than previously believed, and since, IMO, http://xenotechresearch.com/cgi/wp/index.php has demonstrated actual fossils on Mars, I personally consider life on Mars today to be possible. Not certain, possible.
Additionally, continuing research indicates that "junk DNA" is anything but. It appears that it consitutes a reservoir of possiblities. Also, due to its most eccentric orbit and wandering of its axis, Mars periodically goes through lengthy warming and cooling trends, and seems to be in a "global warming" period at this time. Since microbes have been revived after millions of years of dormancy, could not have some life form have evolved to hibernate those periods of time on Mars? Rather fantastic I admit, but by now it's difficult for me to be surprised at the strategies life takes.
Recall also that extremophiles on this planet have demonstrated the most remarkable survival strategies. If microbial life can exist in water more acidic than battery acid, as in the Rio Tinto, might not life evolve to actually use H2O2? It seems to me to be at least within the realm of conjecture, if nothing else. Life is nothing if not tenacious and resourceful.
In any event, I myself am not prepared to entirely write off the possibility of "higher" forms of life, such as crustaceans, on Mars today. The possibilty. As for certainty, that's nowhere close, as I see things.
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Latest (brief) report on this question
research now suggests that Martian dust devils and storms produce oxidants that would render the planet's surface uninhabitable for life as it exists on Earth.
"As a consequence, any nascent life (microorganisms, for example) or even prebiotic molecules would find if hard to get a foothold on the surface of Mars, as the organic material would be scavenged efficiently by the surface oxidants"
Presence of life below the surface of Mars now or in the past is not ruled out by this research.
--similar article headline, from spaceflightnow.com:
Peroxide snow on Mars may make planet inhospitable
The planet-wide dust storms that periodically cloak Mars in a mantle of red may be generating a snow of corrosive chemicals, including hydrogen peroxide, that would be toxic to life, according to two new studies.
http://en.wikipedia.org/wiki/Life_on_ma … xperiments
A re-analysis of the now 30 year old Viking data in the light of modern knowledge of extremophile forms of life has suggested that the Viking tests were not sophisticated enough to detect these forms of life, and may even have killed it in the testing procedure[2]. The central idea here is that instead of being destroyed by Mars' high levels of hydrogen peroxide and other oxidants, life on Mars may use these chemicals to help them survive. For example hydrogen peroxide would stop water in a cell from freezing down to -50°C and is hygroscopic, a useful trait on such a dry planet. The researchers cite Acetobacter peroxidans as a known example of a microbe that uses hydrogen peroxide in its metabolism.
The peroxide is a blessing, because these microbes will not freeze even in -50 degress Celsius temperature.
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There are a few places on Earth where life is practically non-existent on the surface. One is probably the Atacamba (sic) Desert in Chile. Even there, you could dig down and probably hunt up a few microbes.
Rovers have a very slim chance of actually discovering life on Mars, since they only cover a limited area and can't really go underground.
There is very likely some life remaining on the Red Planet, but it's going to be underground. Two places come to mind:
1) Water occasionally wells to the surface on Mars. NASA pictures show it. Recent upwellings, not ancient ones. Look below the source of the upwellings.
2) Below the surface in caves where water still remains.
One general principle about 'life' in any form: If it ever existed, it is difficult to eliminate completely and totally. Assuming there was once life on Mars, to say that conditions have completely eliminated all remaining life is very unlikely. Life in itself is extremely adaptable, once it gains a foothold, and likely impossible to totally eradicate.
One way to look at it is this:
Imagine for a moment that tomorrow morning conditions on Earth changed to the exact conditions on Mars today. Of course...this would be the immediate end to civilization. However, in a hundred years, could you say with any certainty that ALL life, right down to the last microbe, would be destroyed? It is much more likely that SOME limited forms of life would somehow survive. This could be the case on Mars, since it is apparent that conditions favoring life were somewhat more favorable in the past. 8)
There are a lot of extremophilic microbes on Acatama and other deserts on Earth.
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http://en.wikipedia.org/wiki/Deinococcus
Deinococcus radiodurans ("strange berry that withstands radiation", formerly called Micrococcus radiodurans) is an extremophilic bacterium, and is the most radioresistant organism known. While a dose of 10 Gy is sufficient to kill a human, and a dose of 60 Gy is sufficient to kill all cells in a culture of E. coli, D. radiodurans is capable of withstanding an instantaneous dose of up to 5,000 Gy with no loss of viability, and an instantaneous dose of up to 15,000 Gy with 37% viability. It can survive heat, cold, dehydration, vacuum, and acid, and because of its resistance to more than one extreme condition, D. radiodurans is known as a polyextremophile. It has also been listed as the world's toughest bacterium in "The Guiness Book Of World Records" because of its extraordinary resistance to several extreme conditions. Studies are being conducted to verify the origin of D. radiodurans as many scientists are speculating that it has originated on Mars. It has been classified as a Gram-positive bacterium.
It can survive cold, heat, dehydration, vacuum, radiation....
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Im going to have to agree with Mr. Blevins. Life may be further underground where water will have formed caves, pools and underground lakes. There would also be more warmth from the planets core at these depths meaning that if life is present then the process of growing and dieing would create methan gase from the decompossing orginism's. A possible way to find these hidden underground beds is to look for fissures where gas may be seaping out of. This would be a place to start.
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http://en.wikipedia.org/wiki/Life_on_ma … xperiments
PEROXIDE IS NONTOXIC FOR SOME EXTREMOPHILES
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Hi folks,
Just popped in to say hello. Very interesting forum. Have some interesting info to post shortly.
Zydar
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From the point of view of potential future colonisers / inhabitants of Mars - does it matter whether there is some limited microbial life in some underground cave, or not? We already know there will be no animals, insects or vegetation...
What impact would basic life in underground nooks and crannies have, for colonisers?
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It could see the human astronaut as a host; it could be a parasite, it could make us very sick ,,,,,
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It could see the human astronaut as a host; it could be a parasite, it could make us very sick ,,,,,
Yes, but the astronauts wouldn't touch them with their bare hands!
I kind of fail to get excited, scared or anything at all about some microbes!
I suppose the sci-fi horror scenario is that they go completely haywire once they come in contact with oxygen, water or carbonmonoxide (i.e. human habitat).
But really - that could be checked under controlled forms before anyone is exposed to risk, couldn't it? And they could be tested on monkeys, pigs or similar to see if they are parasitic or carries dangerous risks?
The whole "life on Mars" debate seems like much ado about nothing to me. Maybe I'm missing the point - but it won't be conscious life and it won't be able to harm us - so why worry?
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The Sandkings are going to get us!
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martienne, The space suit will not be totally clean when we go back into the habitat where we will take it off so we will be in contact with it at some point.....and even a virus can be lethal
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We went through an argument like this before the moon landings in the 1960's. While they didn't really do it right, the returning astronauts were quarantined for a week or so, from the first couple of missions. Until they figured out there is no life on the moon.
Similarly, we will not know if there is microbial life on Mars (likely subsurface, perhaps quite deep). But simply being there and getting dirty will potentially contaminate the crew, who will be in contact with local materials for anywhere from a few weeks to over a year, depending upon mission design.
We have zero knowledge of any Mars life, but our Earthly experiences say that's likely long enough to show infection by some microbe. This possibility is likely both (1) a potential loss-of-crew outcome, and (2) an indefinite quarantine upon return (begging the question of exactly how to go about doing that).
It would be nice if we actually knew what microbes might be there, but I have seen no instruments designed for any probes (sent or proposed) that could determine what we need to know. For one thing, none dig deep enough.
Extrapolating from what science we do know: for the first billion to billion-and-half years of the solar system's existence, Mars and Earth seem to have been quite similar in terms of geologic history and climate conditions. Once the asteroid accretion bombardment "settled down", both seem to have had thick atmospheres and oceans. The divergence seems to have started about 3 billion years ago: Mars cooled, dried, went salty and acidic, and lost its atmosphere as its magnetic field died; Earth did not.
The time of equable climates with oceans on both planets overlaps the start of microbial life on Earth, and it overlaps with the end of the bombardment; microbial life which seems to have persisted here for approximately 3.5 to maybe 4 billion years. For most of that time, that's all there was here, it was only about a billion years ago (or less) that multicellular forms of life could exist, with the resulting explosion of complex life here. Mars "died" long before that happened here, or potentially there.
Now assume, based on Earthly experience, that life started in Mars's ocean, too. Microbes. Single-cell things.
We have the long-discounted "microbe fossils" in the Allan Hills ALH84001 meteorite from Mars as "evidence". That rock left Mars long after (only 3-5 million years ago), but formed in-place during the time Mars might have had microbial life in its oceans. It wouldn't have been the only such rock with life's materials inside it, that got blasted off Mars during the late heavy bombardment 3.8 billion years ago.
We do know enough from science to know that we cannot dismiss the feasibility of panspermia, as low a probability as successful transport seems to be. The mechanics of gravity wells say that most of the transfer would have been Mars-to-Earth, not the other way. If the assumption is true, then it is thus quite likely that the two microbe populations on Mars and Earth were in fact distantly related.
The 3 billion years since is enough evolutionary isolation to make the fundamental biology quite different, perhaps enough that a Mars virus or germ or whatever could not infect a human. But we cannot know that, until someone is exposed to one. That's the risk.
But, if there is also biological heritage in common (as I suggest there might be), anything we do to create local or global environments on Mars that are more equable will encourage those critters to come back out onto the surface with us. That is something to worry about.
If we go to Mars and there is life down below the surface, we will eventually meet up with it, up close and personal. Depends upon how distant a cousin it is as to whether it can harm us.
I don't see that as reason not to go explore. But it does present great hazards few are yet thinking very seriously about, seems to me. And we will face that same danger elsewhere. Life similar to ours needs a liquid ocean and an energy source to get started. It seems that several bodies in the solar system might fit that description.
I suggest we spend some time formulating a better quarantine method than we had for Apollo.
GW
Last edited by GW Johnson (2015-10-23 10:09:09)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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The space station comes to mind with a new module for the crew to dock to that would work just fine until all the testing is done.
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It occurs to me that an isolation lab on the moon might make more sense, from a certainty-of-containment viewpoint. It's a lot harder to bail out and come home from a facility on the moon than it is from the ISS.
GW
Last edited by GW Johnson (2015-10-25 10:52:19)
GW Johnson
McGregor, Texas
"There is nothing as expensive as a dead crew, especially one dead from a bad management decision"
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If life is found on Mars, it would be the greatest discovery in history. Bring the samples back to Earth. We could use the lab at JSC that was used to contain Apollo samples.
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If Mars meteorites can arrive on earth and potentially carry Mars life, as has been theorised, then earth meteorites should arrive on Mars carrying life. So life should be around on Mars if it is possible for life to exist there, whether or not it originated there. The possibility can not be eliminated, but the probability will reduce as we examine more and more possible habitats without finding life. How to examine lots of possible habitats? Go and have a look.
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I do believe that the methane venting is from underground source that are bacterial in that we did seed mars but with regards to contamination we can not see these so we will not see the ones that could be there that are deadly until we know for sure....we will need to error on the side of caution and send the robotic rovers and probes to find out for sure.....
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Methane on Mars could come from breakdown of clathrate deposits (methane hydrate). The methane spike recorded by a rover may have been caused by disturbance of the surface cover over such a deposit by the machine's wheels. The methane may have originated by volcanism. Its presence doesn't prove that there is or was life on Mars.
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