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"The Dancing Banana Man"
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Judazzz said:
bobme said:
they have proven that life is on mars.
Could you show me where I can find info on that???
Sure ill go look for it if my computer wont crash here.
Its not big life, remeber? they found it? NASA said .. oh well.. i go look for it.
 

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"The Dancing Banana Man"
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Judazzz said:
I'm just wondering: I know NASA has some rocks from Mars with supposed fossilised remains of microscopic lifeforms, but as far as I know that was never substanciated......
The most important result for the detection of life came not from the biology experiment, but from the GCMS. It found no trace of any organic compound on the surface of Mars. Organic compounds are known to be present in space (for example, in meteorites), so this result came as a complete surprise. The GCMS was definitely working, however, because it was able to detect traces of the cleaning solvents that had been used to sterilize it prior to launch.
The total absence of organic material on the surface made the results of the biology experiments moot, since metabolism involving organic compounds were what those experiments were designed to detect. However, the results from the biology experiments were sufficiently confusing to be worth examining.

To reduce the chance of false positives, the biology experiments not only had to detect life in a soil sample, they had to fail to detect it in another soil sample that had been heat-sterilized (the control sample). Had terrestrial life been tested with the Viking biology instrument, the following results would have been expected:

response for response for
sample heat-sterilized control

GEX oxygen or CO2 emitted none
LR labeled gas emitted none
PR carbon detected none

If life was completely absent from Mars, as the GCMS results suggested, these should have been the results from the biology experiments:

response for response for
sample heat-sterilized control

GEX none none
LR none none
PR none none

In highly simplified form, these were the actual results from Mars:

response for response for
sample heat-sterilized control

GEX oxygen emitted oxygen emitted
LR labeled gas emitted none
PR carbon detected carbon detected

The fact that both the GEX and PR experiments produced positive results even with the control sample indicates that non-biological processes are at work. Subsequent laboratory experiments on Earth demonstrated that highly-reactive oxidizing compounds (oxides or superoxides) in the soil would, when exposed to water, produce hydrogen peroxide. Oxidized iron, such as maghemite, could act as a catalyst to produce the results seen by the PR experiment.
Only the LR experiment appears to have met the criteria for life detection, and it does this rather ambiguously. When the nutrient was first injected, there was a rapid increase in the amount of labeled gas emitted. Subsequent injections of nutrient caused the amount of gas to decrease initially (which is surprising if biological processes were at work) but then to increase slowly. No response was seen in the control sample sterilized at the highest temperature (160C, 320F.) While there is still some controversy, the consensus opinion is that the LR results can also be explained non-biologically.

Extinct Life
Most researchers now believe that the results of the Viking biology experiments can explained by purely chemical processes that do not require the presence of life, and the GCMS results completely rule out life in any event. Thus, there is no detectable life at the two Viking landing sites, which were widely separated and different in character (the Viking 2 landing site was specifically chosen because of its high latitude, since it was closer to polar water sources.) While the possibility of "oases" of more favorable conditions for life cannot be eliminated, for example in subsurface permafrost layers or in geothermal vents near volcanoes, the chances that life exists on Mars at the present time do not seem good.
However, we have seen evidence that Mars may have been significantly wetter, perhaps with a denser atmosphere, earlier in its history. If so, there is the possibility that life arose on Mars, only to die out as conditions on the planet worsened. Therefore, some researchers have suggested that future searches for life on Mars be shifted to focus on extinct, rather than extant, life.

On Earth, such extinct life can be found in the form of microfossils and stromatolites. Such forms, as found in western Australia, are the oldest evidence of life on Earth, dating from 3.5 billion years ago. Microfossils are individual fossilized organisms (typically algae), as much as a few millimeters in diameter. Stromatolites are formed when layers of microbial organisms in shallow lakes or pools are covered with sediments. The organisms migrate toward the light after being covered, and the remaining organic material forms a characteristic layered or domed structure.

Stromatolites are important because they may be large enough to be seen by lander (or perhaps even high-resolution orbiter) cameras, and so some researchers have suggested searching for them near features that appear to be ancient lakes or bays. While definitive proof of biological origin would require microscopic imaging or sample return, the discovery of such features would lend credibility to the idea of extinct life.

Conclusions
The question of whether life is common or rare in the universe has deep philosophical implications. It is uncertain exactly how life arose on Earth, so it is difficult to determine how common such mechanisms are. But if life also arose on Mars, this would show that those mechanisms operated not just once, but twice, arguing that life may well be common elsewhere.
However, the search for life on Mars thus far has been unsuccessful. Some portion of the scientific community feels that further searches are a waste of time, while another portion remains neutral or guardedly optimistic. In principle, it's simple to prove that there is life on Mars -- all one need do is find an example. Proving there isn't life on Mars is much harder. Even a prolonged negative search can be countered with the suggestion of yet another, more inaccessible place in which to look.

In the case of Mars, the issue has been complicated by the emotional belief in an Earthlike Mars, which has largely been shown to have been a myth. Mars is a spectacular place, and will remain so even if it is finally proved to be lifeless. Today, we don't know for sure if there is or ever was life on Mars. But one thing is certain -- one day, there will be.
 

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"The Dancing Banana Man"
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Judazzz said:
bobme said:
However, the search for life on Mars thus far has been unsuccessful.
I think this says it all.

Btw: were does this info come from (ie. what source?)?

And other btw: dude, this post contains more words than all your 1160+ previous posts together
Nasa.
and shad up about that
 

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"The Dancing Banana Man"
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MPower said:
How could we be the only beings. There has to be another life form out there.
yea i meen we dont even know all life forms on our earth, who knows whats out side of it.
 
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