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Martian Microbe Fossils, Not So Debunked Anymore
rubycodez writes "Three meteorites, including one that has been in a British museum for over a century, are going to be put under the electron microscope and ion microprobe by NASA. We're 'very, very close to proving there is or has been life [on Mars],' said David McKay, chief of astrobiology at Johnson Space Center."
Undebunked? Rebunked? Or just bunked?
Only three things are certain; death, taxes, and apocryphal quotations - Ben Franklin.
http://www.scientificamerican.com/article.cfm?id=proof-of-martians-to-come-this-year-2010-01
we here on earth are all alone in the great big dark.
If that's true, it's an awful waste of space.
I just had a psychic vision of the future. In my vision, this test ended up either producing negative or inconclusive results--once again disappointing the millions of believers who just cannot accept that, for all practical intents and purposes, we here on earth are all alone in the great big dark. I also see myself posting a link this this very post, a year or so from now, in yet another similar thread that has the believers once again futilely hoping that the discovery of life out there is "very, very close."
I think what you're witnessing isn't some X-Files Want to Believe style cult assembly or circle jerk but instead the simple fact that should this be confirmed, it changes everything. From not only a scientific point of view with the near complete annihilation of Drake's equation but also from a philosophical and -- perhaps most importantly -- theological point of view. Since the gravity of a decision in the positive direction is so great, the tiniest disturbances in the canon of thought surrounding extraterrestrial life gets close attention by the nerd world. Even the minuscule announcement that in a certain amount of time we will know with 100% certainty one way or the other on these fossils is actually newsworthy.
Similar to the anti-global warming decision. Huge consequences mean massive attention.
My work here is dung.
...this topic. Any here on Slashdot?
For example, how did we determine that Allan Hills 84001 came from Mars and not anywhere else? Not even a Mars-like planet in a nearby solar system? How?
How do we know that the signs of life on that rock are from before it was landed, rather than after? I see wikipedia mention that 'some argue', but there's almost no meat on these bones.
There are more questions, but I guess I'm uncomfortable with the word 'prove'. If this were in a court of law, for example, all of this would be 'circumstantial'. There generally needs to be a lot of it, and it needs to be compelling, before this sort of evidence would get a verdict. This leads me to suspect one of these scenarios:
A) There's more detail here. (I'm rooting for this one)
B) The scientific word 'prove' isn't the same as other uses of 'prove' (which would be sad, since they already have their own words - e.g. hypothesis)
Anyway if you either are a third party with sources or someone who actually works with this kind of thing, please do comment below. I'm in the mood to learn something today.
I think the baby Jesus put those "microbes" there to relax after a hard day of burying fake dinosaur bones.
Well I could give a crap about theology. What I want to know is some of the biochemical properties of these organisms. Did they use DNA, RNA or some entirely different set of molecules of protein encoding? Did they share a common ancestor with life on Earth? Is it possible that life had evolved on Earth prior to the collision with the Mars-sized body that produced the Earth, and we have a sort of limited panspermia going on (or maybe it's visa-versa, maybe life began on Mars)? If life was on Mars, is it quite possible as its atmosphere slipped away and its surface became incredibly hostile that somewhere below their surfaces, or perhaps even in deeper valleys and rift zones like Valles Marineris, where atmospheric pressure would be higher and the potential for a more habitable zone might be found?
Of course, this infinitely increases the potential for life elsewhere in the solar system. Europa becomes target #2, and, potentially a far more likely place than Mars to find a complex ecology.
I suppose, in consideration of theology, it depends on who you're asking. Some of the IDers (Michael Behe and his ilk) and Theistic Evolutionists (Catholics tend to this one) will not have any epiphanies. For Old Earth Creationists, it probably won't sway them. But YECs, well, that's a group who has heavily painted themselves into a corner. Now, on top of having to claim the earth is only 6,000 years old, they have to deal gyrations over the age of Mars. They'll probably start by denying all of it, claiming it to be a hoax by evil evilushionists. Then they'll come around to the idea that God planted life there, but no later than 6000 years ago! The people who will change views are the fence sitters at any of these levels.
As for space exploration, well the push for a long-term manned mission to Mars is going to get a major bump. We simply do not have the probes complex enough for more than a bit scouring of the few top inches of Mars' crust. I'm not putting them down, the Mars Landers have been an overwhelming success, but the kind of science any probe sent there, or any probe they're planning to send there, is still pretty limited.
Maybe we should put off any notions of getting humans there in the next two or three decades, and stretch it out to 2050 or 2060, working on self-sustaining long-term bases for humans, so we can send people there for a few years at a time. I'm sure you would have no lack of volunteers among the scientific community.
The world's burning. Moped Jesus spotted on I50. Details at 11.
Drake's equation has quite a few terms in it and only two of those terms are subject to reevaluation: the average number of planets per star that are suitable for life, and the fraction of planets which are suitable for life that actually have life.
Could also be added that Mars and Earth could have a common source of primordial life, and/or that samples from one crossed over to the other. Far greater would be the impact IF life on Mars turned out to be so radically different from Earth's as to preclude any sort of common ancestry.
The Long Now Foundation
Disclaimer: I am a planetary scientist but do not work directly on the martian meteorites.
1) We know that the rocks are from Mars because they all have consistent isotope ratios between the various meteorites that are inconsistent with those isotope ratios on Earth but consistent with isotopic ratios on Mars
http://wapedia.mobi/en/Neutron_activation_analysis
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V6T-41WBDHD-8&_coverDate=10%2F31%2F2000&_alid=445411040&_rdoc=1&_fmt=&_orig=search&_qd=1&_cdi=5823&_sort=d&view=c&_acct=C000053194&_version=1&_urlVersion=0&_userid=1495569&md5=1c1b0d04dba7f06365b072655bef68b3 (May need a subscription)
2) The age(s) of the possible fossils are greater than the time the meteorites have been on Earth. Again, this can be calculated using various isotope ratios. In essence, these things formed while the rocks were still on Mars.
3) I agree with your discomfort with the word "prove." Most scientific study is based on the Popper philosophy of disproving something rather than proving its opposite.
A) The new instrumentation and techniques being used on these meteorites are greatly advancing our understanding of them. The press announcement that AH84001 might have evidence of life was premature (what we call "science by press release"), but the publications by the team were certainly good and valid work, whether they are falsified or not...
B) The scientific word "prove" is more about the lack of any valid competing hypotheses. If you can't come up with a reasonable alternative explanation for the data, you have to accept the presented explanation.
Woah woah woah! Hold the phone. What do you mean unicorns don't exist?
WTH is this thing then?
http://zuill.us/andreablog/wp-content/uploads/2009/05/uni-corn-lrg1.jpg
Answer me that, smarty pants! ;-P
Sent from your iPad.
We also have horses too, and numerous stories of magical ones with horns. That's way more evidence than we have of any alien life.
Huh?
We have people, and numerous stories of people from other worlds. So I'd say the amount of evidence is about equal. XD
Bow-ties are cool.
The universe is just too big and vast for this to be the only planet with life on it.
Estimates are what these days for # of galaxies? Hundreds of billions? You telling me we're the only ones out here?
I don't buy it.
Life, maybe, but would there be multi cellular life?
For the first 3 billion years of life on earth, there were only single celled organisms. This time span is in the same order of magnitude as the estimated timespan that life is possible on earth. If life on an earth-like ends a little early or starts a little late, life may never evolve from the goo stage.
And think of some of the extremely rare occurrences that need to coincide to make it possible for life to exist so long on a planet.
Jupiter has kept the inner planets to some extent from bombardment, by sucking up asteroids in its enormous gravity well. Without this long distance Jupiter, the earliest time that life would have been able to exist might have been pushed forward significantly. In extra solar planetary systems discovered so far, it seems that a hot Jupiter, close to the star, appears to be the norm.
Liquid water isn't stable on normal rocky planets. Too far from the star, and it just freezes. Too close to the star and water gets photolysed into hydrogen and oxygen, the oxygen getting bound in the soil and the hydrogen getting stripped away in the solar wind. The earth still has some of its water left, because it is unusually dense and has a magnetic field that protects it somewhat. Both the density and the magnetic field were made possible by an unlikely event: the early earth collided with another planet of similar size. Much of the lighter material got ejected and formed the moon in a low orbit, while much of the denser, metallic material formed the earth. Other planets in the solar system have no magnetic field to speak of. Venus lost its water due to being too close to the sun, Mars lost it due to its low density. Our large metallic core has at least one other effect essential for long lasting life: decay of radio active isotopes keeps it warm and liquid, and keeps the crust thin enough for plate tectonics to be possible. As life does its thing, CO2 gets locked up in the crust in the form of limestone and fossil carbon. Without plate tectonics and the resulting vulcanism, this carbon would not have been recycled back into the atmosphere, causing early life to run out of fuel. As the sun was a lot cooler than it is today, the removal of CO2 from the atmosphere might have caused the early earth to freeze. As the sun gradually gets hotter over the course of its lifespan, this also puts an upper limit to our existence. About a billion years from now, it will likely be too hot for liquid water to exist on earth. A billion years seems like a long time, but that would mean that some two thirds of the time period in which life can exist on earth had already passed before the first multi cellular life forms are known to have arisen.
Our unusually large moon has also served to stabilize the rotation of the earth. Without it, the earth may occasionally have been near-sterilized whenever one rotational axis pointed towards the sun, causing one hemisphere to burn to a crisp, and the other to wither in a frozen darkness for god knows how many thousands of years. The moon, when life was in its early stages, was a lot closer than it is now, causing the difference between low and high tide to be in the order of maybe a mile. This would have covered much of the earth's surface with tidal pools at some point in the day, and tidal pools are believed to have been pivotal in the development of photo synthesis. Other planets we know of have moons that are far smaller in size, relative to the planet they orbit.
The argument that I find most convincing is the observation that even here on earth, multi cellular life seems to hold only a tenuous advantage over good old single celled organisms. Single celled organisms have been dominating the world ever since life began, about
it would only take a few hundred million years (blink of an eye in cosmological terms) to probe the entire galaxy
But what good would that do us? A few hundred years is all it takes on earth for technology and language to change, empires to rise and fall. A few thousand years buries entire civilizations in the sands of time. Passage of one million years would result in evolution of the human race into something that we only superficially resemble today. Ten million years wipes species from the map, replacing their line with another. A hundred million years from now, if one of these probes responds back to us, would we be here to hear it? Would our descendants resemble us any more than we resemble a trilobite? If so, would we even recognize the transmission as ours, related somehow to ancient myths of the far distant past? Be able to decode it, and understand its message?
I prefer rogues to imbeciles because they sometimes take a rest.
What makes me very dubious about these claims is that the structures are so small that they'd have to be nanobacteria, and yet the so-called "nanobacteria" on Earth turn out to be non-living.
No. One does not have to accept an extraordinary scientific claim just because one does not yet have another explanation. There is lots of data on UFOs. For some of this data, there is no reasonable alternative explanation. That doesn't mean that I have to start believing in UFOs. It just means that UFOlogy is a field where the data are all a big pile of doggy doo. Science has many subfields in which the state of the art is so terrible that reputable people don't want to get involved, and no progress is being made. Two good examples that spring to mind are nanobacteria and IQ testing.
I am very skeptical about extraordinary scientific claims coming from NASA. NASA has not succeeded in instituting a culture of proper scientific peer review. For instance, the Breakthrough Propulsion Physics Project does crank stuff, and has ties to characters like Harold Puthoff, who specializes in things like telepathic visits to Jupiter. In a way it's not surprising that NASA has problems with proper peer review. They're the handmaiden of Congress. Congress wants the crewed space program to be run as a national prestige project, but they also want to be able to give justifications for the crewed space program that don't sound like pure nationalism. Therefore they coax NASA into coming up with bogus scientific justifications for programs like the shuttle and the ISS. In a culture that's all based on puffing up bad or nonexistent scientific achievements, it's not surprising that they're susceptible to kookiness.
Extraordinary claims require extraordinary evidence. It is not sufficient to say that there is no alternative explanation for these structures in the meteorites, and therefore they must have arisen from living organisms. No geologist has ever been to Mars. We know far less about Mars's geological history than we do about the earth's. It's not at all surprising that we find geological samples where we can't explain how they were formed. That doesn't mean that we immediately have to leap to the conclusion that they were made by nanobacteria.
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