New Study of 1980s Mars Meteorite Debunks Proof of Ancient Life On Planet (theguardian.com) 32
An anonymous reader quotes a report from The Guardian: A four billion-year-old meteorite from Mars that caused a splash here on Earth decades ago contains no evidence of ancient, primitive Martian life after all, scientists have said. In 1996, a NASA-led team announced that organic compounds in the rock appeared to have been left by living creatures. Other scientists were skeptical and researchers chipped away at that premise over the decades, most recently by a team led by the Carnegie Institution for Science's Andrew Steele. Tiny samples from the meteorite show the carbon-rich compounds are actually the result of water -- most likely salty or briny water -- flowing over the rock for a prolonged period, Steele said. The findings appear in the Science journal.
During Mars' wet and early past, at least two impacts occurred near the rock, heating the planet's surrounding surface, before a third impact bounced it off the red planet and into space millions of years ago. The 4lb (2kg) rock was found in Antarctica in 1984. Groundwater moving through the cracks in the rock, while it was still on Mars, formed the tiny globs of carbon that are present, according to the researchers. The same thing can happen on Earth and could help explain the presence of methane in Mars' atmosphere, they said. But two scientists who took part in the original study took issue with these latest findings, calling them "disappointing." In a shared email, they said they stand by their 1996 observations. "While the data presented incrementally adds to our knowledge of (the meteorite), the interpretation is hardly novel, nor is it supported by the research," wrote Kathie Thomas-Keprta and Simon Clemett, astromaterial researchers at NASA's Johnson Space Center in Houston. "Unsupported speculation does nothing to resolve the conundrum surrounding the origin of organic matter" in the meteorite, they added.
During Mars' wet and early past, at least two impacts occurred near the rock, heating the planet's surrounding surface, before a third impact bounced it off the red planet and into space millions of years ago. The 4lb (2kg) rock was found in Antarctica in 1984. Groundwater moving through the cracks in the rock, while it was still on Mars, formed the tiny globs of carbon that are present, according to the researchers. The same thing can happen on Earth and could help explain the presence of methane in Mars' atmosphere, they said. But two scientists who took part in the original study took issue with these latest findings, calling them "disappointing." In a shared email, they said they stand by their 1996 observations. "While the data presented incrementally adds to our knowledge of (the meteorite), the interpretation is hardly novel, nor is it supported by the research," wrote Kathie Thomas-Keprta and Simon Clemett, astromaterial researchers at NASA's Johnson Space Center in Houston. "Unsupported speculation does nothing to resolve the conundrum surrounding the origin of organic matter" in the meteorite, they added.
Itâ(TM)s a plot (Score:1)
Maybe cookies (Score:1)
I've read this post before on this site.
Much of what you experience *could* be explained by blocking cookies. I say this because my normal browser (Firefox) is set to block all cookies, except for a few that I hand entered to allow purchasing (slashdot, eBay and paypal, mostly). It also blocks javascript.
I have one install that blocks cookies for normal browsing, and another browser install (Chrome) that I keep open and that I use when I find a site that I really need to view a site that requires the cookie
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It's unlikely you've read that exact post. It is a bot-generated random list of complaints from a much larger pool. It's doubtful the bot-writer ever had any of those experiences because nobody who had had those experiences (and thus were technically unaware) would have had the technical skill to write a bot. And if they had, they'd be publishing the same list each time and not a randomly generated one.
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No, they are not your experieces (Score:2)
Nobody cuts and pastes random "incidents" into messages, or spams a news for nerds site, when they have something genuine. Nothing in this barf of a message is real, it is bot-generated nonsense designed to block the legitimate use of a site.
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Go to Mars, try their internet
Hopefully Webb (Score:2)
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Yes, it has some spectroscopy capabilities, but not the high-precision green-red (visible) spectroscopy that is most likely to reveal the presence of a chlorophyll-analogue. Or the near-UV spectroscopy needed to detect an ozone absorption as an indicator of an oxygenic atmosphere (not that oxygen-production is a necessary part of "life",
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The design spec for JWST is very largely about distant, highly red-shifted galaxies.; It may be of some use for exoplanet work, but the reduced resolution of IR observation isn't going to help with that (compared to existing visible light tools, including ground-based AO systems).
There have been proposa
Misleading headline (Score:2)
The headline is obviously misleading, like most headlines these days. If it read, "attempts to debunk" it would be a bit more honest. What the study does is present a competing theory and highlight the need for more samples.
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You sound remarkably like intelligent design proponents when confronted with yet more evidence against what you want to believe.
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Intelligent design is an unfalsifiable "explanation" that doesn't qualify as a theory for many reasons. The fossil theory is still a perfectly good theory, it just isn't now the simplest theory that explains all known facts and therefore isn't the theory we should be looking at first. It has not, however, been falsified by this new finding. It's merely a much less probable explanation.
To many, that might well be considered splitting hairs, or indeed the atoms in hairs, but the difference does matter. A fals
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That certainly wasn't my intention. I don't actually think that it's more likely that the origin of the anomalies in these samples is life rather than some other process. All I was saying is that an alternative theory doesn't "debunk" the original one. This is just an alternative theory of formation. There simply isn't enough evidence with just the one sample. It's also not a binary choice just because there's one alternative explanation. There could be a dozen more alternate explanations that have not been
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Life as an explanation for it is definitely a long shot. I don't think this theory is necessarily more likely though. My main issue was simply with the headline. It would be nice if science headlines, at least, would try to avoid sensationalism. It doesn't "debunk" anything. The life explanation was always dubious. This is just an alternative explanation. What we need are a lot more samples.
What about the "worms"? (Score:2)
The article focuses on chemical analysis. But what about the microscopic "worms" they found in it? Organic chemistry doesn't always fossilize such that showing that the organic compounds could have a chemical (non-life) origin doesn't mean the worms were not living.
It's speculated the worm shapes were "carved" by magnetic forces instead of life, but the actual cause has never been settled to the best of my knowledge, and thus the worms are still an unsolved mystery.
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It reminds me of Occam's Razor. The original version; God waving His hand Miraculously is a simpler explanation for all that we see around us than science, and therefore is the preferred explanation.
It's simpler, sure; but as it fails to actually provide explanation, it fails to establish what the necessary elements are. Therefore, it completely fails under the modern formulation of Occam's Razor. It simplifies by assertion. Of course this gets confusing, since the modern Occam's Razor is basically just sci
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It is what decades of geology students have been caught by in their field trips (and sometimes in exams) - a "pseudo-fossil" - a thing that looks like a fossil, but isn't. You get warned about such things, and reminded to check your assumptions.
Now that's got
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> someone had shown that you can generate such carbonate mineral growths without the presence of life in the experimental set up.
I've never seen photos of the lab version of the tubes.
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Whether or not the McKay et al "worms" were pseudo-fossils or not was one of the first things I thought of on reading the 1996 paper, because they're not exactly replete with the sort of detail you'd expect from a fossil - even a microfossil. Pseudofossils are something you always consider as a possibility when you have something you
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> I don't know of a single geologist who has been convinced by the 1996 claims
I agree healthy skepticism is warranted. But I've yet to see evidence known natural and/or lab-created rocks can produce something similar. This is not "proof" that the "worms" are Mars life, only that the worms are still a very open mystery.
There may be a reason they don't want to show their lab simulations: they perhaps only very roughly compare. If they were a dead ringer, they'd likely have paraded them around to the press:
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You're free to believe that. But your opinion is likely to be completely ignored when it comes to the decisions over where to allocate exploration budgets.
There is a belief that science ought to be some form of democracy, where everyone's opinion matters as much as everyone else's. Call me if that ever happens and I'll hold your beer while you demand the re-opening of the "worms mystery", but I'll probably be dead decades before then.