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The Indirect Case For Life On Mars
Deinhard writes "Space.com is reporting that '[a] pair of NASA scientists told a group of space officials at a private meeting here Sunday that they have found strong evidence that life may exist today on Mars, hidden away in caves and sustained by pockets of water.' It is all based on methane signatures and not direct observation. Now plans for using the Genesis Device on Mars are out ... unless this is just a particle of preanimate matter caught in the matrix."
If ancient life can be discovered under Antarctic ice, nothing is unpossible.
Given our accessibility and coverage on earth, we didn't know about this ancient life until recently.
And now we only have few rovers on Mars...
Rock that crushes, Paper & Scissors that don't matter.
I do hope that this isn't another false alarm. This comes at about the same time as this odd lichen-like feature was photographed: http://www.space.com/scienceastronomy/mars_life_05 0216.html >. Fascinating developments.
On a slight tangent, I wonder if Larry Lemke is related to the savant Leslie Lemke.
Eh?
Years ago we were told that the best place to find life on Mars would be under rocks where there could be lichen-like lifeforms. It would shield them from the harmful UV and solar radiation effects. But so far JPL hasn't used the Instrument Deployment Device (the remote "arm") to turn over a rock and examine what's under it with the microscopic imager. They've looked all over the exposed surface of rocks and even dug small trenches in the soil and examined that. Perhaps they don't want to break it, but still I would like for them to at least try to look under a rock or two. There might be something interesting there!
Unless a Martian creature suddenly appears within either of the camera viewfinders of the Mars probes Spirit or Opportunity and decides to ham it up.
Personally, I'm of the opinion that Martians shot down the NASA Mars Polar Lander and the ESA Beagle 2 8^)
According to http://www.newscientist.com/article.ns?id=dn7014 the scientists have not only detected methane, but also formaldehyde, which was measured at levels of 130 parts per billion. From the article:
He thinks that the gas is being produced by the oxidation of methane and estimates that 2.5 million tonnes of methane per year are needed to produce it. "I believe that until it is demonstrated that non-biological processes can produce this, possibly the only way to produce so much methane is life," he says. "My conclusion is there must be life in the soil of Mars."
Bruce
I wonder how far the nearest cave is to the rover's current position? Does the rover have a flashlight?
Exactly. Which is more likely to find life on mars - sending a stack of insturments to one spot on Mars (with the benefits of reduced latency and perhaps better local navigational ability - the two benefits that humans provide), or sending 50 stacks of insturments (with the option of having different insturments in each group, and the further benefit that you can stagger launches and thus send higher-tech insturments on each successive trip) each to different parts of the planet?
Heck, there's even proposals for robotic missions to "hop" across wide ranges of Mars via multiple takeoff/landing cycles, taking samples and examining the soil in each location. Such a mission would be many times more expensive if it had to carry humans, life support, food, etc, but is feasable for a robot-only mission.
Really, the only thing humans get you is slightly better local mobility and much reduced latency, and neither of those are particularly critical issues. The "baggage" that comes with people - tons of food, water, air, shielding, housing, etc - can't really justify the mobility and latency benefits.
"Well, then fire it up and show me what this..." (sigh)
and that is why humans will need another planet to live in the first place , because we dont respect the "lower" lifeforms
what WILL be gained now WILL be your doom tomorrow
"Humans are like virus"
and after mars? where will we go?
I think it's the significant temporal VARIATION of methane content in the atmosphere of Mars that is peaking interest in this theory, not just the presence ot methane.
Evidence of methane and its coverage with water can be expained in at least one trivial way. Note Mars atmospheric composition:
C02: 95%
H2O: 0.03%
Now huge ultraviolet radiation breaks down H2O and CO2 to loose hydrogen/oxygen/carbon atoms (this process along with mars weak gravity is co-responsible for mars losing its once dense atmosphere). Additionally there is huge evidence of Electrical Discharge On The Martian Surface
Try simple high school science project: Load a container with water and CO2, add electrodes to create some discharge ('lightning') and you'll have your own PanGea in a bottle.
After some time all sorts of 'organic' chemicals will be present in the bottle along with most common methane (but also alcohols, higher carbohydrates and more complex molecules). I would think decent scientist would at least mention such possibility in reocurring articles on 'OH-OH methane is evidence of life on mars'
Actually, the deal with the methane is this:
Its lifetime in the atmosphere is ~ 350 (earth) years. Thus, for the amount of methane detected, either there was recent (years ago, not Ma or even Ka) volcanic activity, or there is life currently producing the methane. Either of these two speculations is valid.
Your other suggestions are valid also, but require something to help them release their trapped methane. Ices/clathrates need to be melted, which means they need energy input. Hydrocarbon deposits would require life to have existed in the past, and would require something to release just the methane form rather than a bunch of other stuff. i.e., we would see other (than just methane) evidence for a degassing hydrocarbon resevoir.
The volcanism argument is very difficult to sustain because we don't see evidence for it NOW (however, as my advisor is always looking for opportunities to point out, "absence of evidence is not evidence of absence."). I like the volcanism argument because I like volcanism, but the most recent flow fields are 10 Ma, and seem to have been the last gasp of a dying planet. Unless they released a LOT of methane into the atmosphere, the current methane is not from those flows.
The life argument has some major problems, but it's at least worth investigating. There needs to be some sort of energy to maintain these putative methanogens, and that's one of the issues right now (we don't know where to look for life because we don't see any* evidence for subsurface energy).
We can't directly look for concentrations of methane because the in situ measurements would provide something like 1 PPM, and averaged through the atmosphere would be undetectably low compared with the amount of the methane in the (presumed well-mixed) atmosphere (ppb).
* There are small east-west trending fissures (canyons) that may be the best places to search for life-sustaining energy because they collect daytime sunlight but don't effeciently reemit it at night, thus increasing their temperatures relative to the surroundings and possibly conducting heat to the subsurface and possibly collecting enough heat to sustain life. . . I'll let you know in a week or so if this pans out. . .
And as such, methane hydrates or underground hydrocarbon deposits would vary over time as well. In fact, I can't think of an inorganic methane scenario which *wouldn't* be affected by, say, temperature.
"Well, then fire it up and show me what this..." (sigh)
...what if we brought life to mars?
Those who know, do not speak. Those who speak, do not know. ~Lao Tzu
You said: "IIRC, Mars is geologically (or "areologically," if you prefer) dead -- obviously it had significant volcanic activity a long time ago, as evidenced by Olympus Mons, but none that we've ever detected going on now or in the recent past."
The idea that Mars is geologically dead is based on old data. After the Mars Global Surveyor mission, alot of new information came about. One of the estimates was that Mars had volcanic activity about 20 million years ago. Considering a 4.5 billion year existance, 20 million years is hardly dead. This data was from crater counting. Older structures will have many craters and younger structures will have few craters. Obviously this has a fairly large margin of error (but a 2 billion year old structure still won't be confused with a 20 million year old structure). New studies from the Mars Express mission have said that vulcanism may have occured as early as 4 million years ago. This tends to support the idea that volcanos on Mars are dormant, not dead.
As far as having a magnetic field or having plate tectonics, yes Mars is dead. Mars may have had plate tectonics (which in general is due to convection of the mantle) in one localized region in its early history, but there is no evidence of it now.
Recent studies of gullies, volcanism, and the planet's precession tend to indicate that Mars may be alot more active than we think.
Suddenly, the hairy finger of a familiar monkey tapped me on the shoulder. It was time.--G. T.
Scientists releasing papers and ideas, especially ones that are obviously controversial, before the peer review/publication process has been completed is poor science. While the peer review process is not perfect with the potential to overemphasize mediocre/bad work or miss good work, the system is the checks and balances upon which science has relied for decades to ensure quality work.
For an example of how releasing scientific results to the media before it is fully evaluated can have disastrous effects, check out cold fusion.
Decades ago, a treaty was signed stating that Antarctica would be used for scientific purposes only.
Also, terraforming there would not be a good idea. We would have to warm up the climate, and before the temperature would rise, the glaciers there would melt, raising the ocean level significantly. The resulting death toll would make the recent tsunami look like a small splash. The same thing goes for draining the Mediterranean. The water has to go somewhere.
Eventually, we will have to expand out into space, if not for practical reasons (natural resources, living space), for psychological purposes. Throughout history, people have constantly been going west because of the belief that it was their duty as humans to control the land out there, an idea commonly known as manifest destiny. Now, if we go any further west, we'll end up in the Far East. The only direction lefr is up.
An entire universe is out there to explore and bring civilization to. All we have to do is grab it!
...making the indirect case for the existence of God. This is all very well and good from an "armchair philosophy" standpoint, but until I see electron micrographs of the native Martian fauna (or flora?), I won't believe there's anything alive there except any stray bacteria trapped deep within Terran probes (I'd say "Earthling probes", but that'd sound even sillier, not to mention like it's something that probes an Earthling...)...
With spending like this, exactly what are "conservatives" conserving?
But we do know that there is a small amount of commerce of material between Mars and Earth without the use of space probes. Well, a billion tons has moved from Mars to Earth (see here). It's much harder for stuff to move the other way but it's not completely implausible. (It would require quite a kick of energy from somewhere, not just to get it out of the earth's gravity well, but also to push it out from the Sun. But it could get that by looping around other planets - eg. Venus. The journey might take many tens of thousands of years. But it's not impossible.)
Doesn't it make you feel good to know that our freedoms are protected by politicans, lawyers and journalists.
Jeez, this is so transparent.
Not necessarily. Back in the 1960s James Lovelock (of Gaia Hypothesis fame) was working for NASA on detecting life on other planets. He reasoned that to detect life all you needed to do was to see if the atmospheric chemistry was far from equilibrium. He used Earth as his example explaining that the presence of highly reactive oxygen and other clues indicates life. He suggested to NASA that a 1000 inch telescope be built to get detailed chemistry information on the other planets to determine if there was life without the need to send probes. NASA turned it down.
So the presence of methane on Mars is not a trivial thing.
Is the "possibility of life" a grant magnet? Of course, so is cancer, HIV, etc. Doesn't mean they don't have something important to say.
Bitter and proud of it.
When it becomes easy...
well, yeah... that's the clincher, innit? How the hell is it ever supposed to become easy if we keep putting it off?
I know there's a lot of reasons - some good and some bad - for why we should send a manned mission, but for me the most important reason is that we need to learn how. And we need to start learning NOW.
It's not just about figuring out what color the sky on Mars is or if there's life in them thar hills - hell yeah, we can send a TON of bots up there to tell us that. But its a lot more than that... as a species we are literally trapped at the bottom of this gravity well and we're in serious danger of ending our days here. The sooner we get off this rock the better our chances of survival will be.
Learning to life and survive in space and on other planets is not going to get any easier or cheaper by waiting for some future to come of its own accord - we have to make it happen first. It's our experience and fine-tuning that makes anything cheaper and easier. You don't get 500Ghz processors with terabytes of RAM to build PC's with until you've cranked out a lot of 286's and 386's first.
It takes an idiot to do cool things - that's why it's cool!
It wasn't so much that the results from the other Viking experiments were inconsistent with life -- they weren't -- but that they could be explained by non-life processes (such as superoxide chemistry). The labeled-release experiment's results required a lot more handwaving to be explained that way.
I used to explain that the Viking biology experiments package was very carefully designed to answer the question "is there life on Mars?". The two Vikings landed, carefully performed their experiments, and broacast back the message "could you repeat the question?".
Of course, if Martian soil were that rich in superoxides, it's hard to imagine methane lasting even 300 years.
-- Alastair
I do agree that it's a hard choice to make, send humans to Mars or send more probes to interesting places like Titan.
But I think that long term, it's far more useful to have an extended manned presence through the solar system that will enable even more such missions than we might be able to manage only from Earth. Not to mention the mental boost we would get from really having a permanent human presence on Mars itself. It's a question of sending many questionable one-off mission rather than increasing the base of our reliable capability to send even unmanned missions.
I really recommend Zubrin's book for a very sober view of how we can get to Mars realistically. Indeed they are currently engaging in terrestrial-based experiments that address a lot of the little but crucial small practical details of the effort.
Although I am pleased with the current direction of the space program, I think the timeframe for that effort is rather long and I fully believe it will be a private mission that lands on Mars in about fifteen to twenty years or so.
"There is more worth loving than we have strength to love." - Brian Jay Stanley