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Adding water to Martian soil samples might have been a bad idea
- generalizations 3y agoI'm surprised that only the Viking lander bothered to test for signs of life - especially since the results were "confusing".
- Guvante 3y agoIIRC we have been avoiding going anywhere where life could be to avoid contamination. Making a lander where we know there are no earth microbes on it is quite difficult and certainly important for testing for life.
- qup 3y agoWhich places did we avoid going?
- tcoff91 3y agoprobably europa and enceladus
- ralferoo 3y agoAll these worlds are yours. Except Europa. Attempt no landing there.
- zokier 3y agoFor example from the Mars 2020 mission (Perseverance rover) landing site selection: https://marsnext.jpl.nasa.gov/scieng_plantary.cfm https://marsnext.jpl.nasa.gov/scieng_plantary.cfm > A Special Region is defined as a location where the temperature could exceed -28° Celsius (-18.4° Fahrenheit) and water activity is at least 0.5. Water is key to life as we know it, and water activity considers the availability of water and water vapor as a potential support for life processes. > The Mars 2020 mission is restricted from landing in, entering, or creating, a Special Region on Mars [...] > Thus, the Mars 2020 mission is also restricted from landing in sites where scientists suspect water, brine, or water ice could be present, or could be induced, within 5 meters (about 16.4 feet) of the surface
- asdff 3y agoIt takes them seven months to fly a rover to mars. They could potentially devise a way to expose the rover to space during these months to sterilize it.
- tastyfreeze 3y agoRovers are assembled in a clean room and space doesn't sterilize all life. It is impossible to know with certainty that a rover is sterile. Even autoclaving the whole rover doesn't guarantee sterility. https://www.sciencealert.com/a-bunch-of-earth-organisms-were-stuck-outside-the-iss-and-survived https://www.sciencealert.com/a-bunch-of-earth-organisms-were...
- asdff 3y agoThere has to be some limit on radiation resistance for these microorganisms. At the end of the day, DNA is a fragile molecule and it can be degraded. Maybe the rover could be overbombarded with radiation on this journey, if the background radiation in space is insufficient.
- tastyfreeze 3y agoWe have found life in every environment we have explored on Earth. That includes surviving high radiation environments. https://en.wikipedia.org/wiki/Deinococcus_radiodurans https://en.wikipedia.org/wiki/Deinococcus_radiodurans
- asdff 3y agoRadiodurans probably still has some limit where the rate of radiation is higher than its ability to repair fragmented DNA, at which point things snowball and the DNA is quickly broken down to its constituent bases and there would be no template at all in which to initiate any repair.
- sbierwagen 3y agoThey haven't bothered with labeled release or adding water to soil. Curiosity does have a similar oven+GCMS setup to Viking, which has indeed found funny organic chemicals in some soil samples: https://en.wikipedia.org/wiki/Sample_Analysis_at_Mars https://en.wikipedia.org/wiki/Sample_Analysis_at_Mars
- sproketboy 3y ago[dead]
- NegativeLatency 3y agoStill waiting for a sample return mission
- inciampati 3y agoIt's true. What a challenge!
- andix 3y ago[flagged]
- seanw444 3y agoFor good reason.
- chargingmarmot 3y agoPlease. We live on a planet that has been bombarded by space rocks for billions of years and that's home to all sorts of viruses and bacteria that have been evolving to kill us for as long as we've been around. If Mars were covered in gray goo we would have noticed by now.
- Calavar 3y agoSo did the indigenous people of the Americas, and yet it's estimated that as many as 90% of them died within the span of about 150 years.
- chargingmarmot 3y agoThis just reinforces my point. The germs that killed the native Americans grew up in an environment where humans were living in close proximity to a variety of animals (cows, chickens, rats) for thousands of years. (cf. https://en.wikipedia.org/wiki/Guns,_Germs,_and_Steel https://en.wikipedia.org/wiki/Guns,_Germs,_and_Steel)
- andix 3y agoThey are talking about cells, but must every form of life be built from cells? It seems like all life on earth descended from one species, that was a cell. So all our life on earth is made out of cells. But couldn't life be completely different somewhere else?
- timacles 3y agoA cell is just literally an organic unit. It’s something organized that is alive. Any living thing would have to have cell’s otherwise it’s just not organized in any way which doesn’t make sense in the context of our universe
- etskinner 3y agoThis is very close-minded thinking, it's very possible life doesn't require cells
- adrian_b 3y agoIt is very likely that some kind of life that doesn't require cells must be possible, because it must have existed before the appearance of cells. Cells are much too complex to appear spontaneously, without evolving from an acellular form of life. Cell membranes can form spontaneously from fatty substances, but no cell can live without complex molecular pumps that are embedded in the cell membrane and which bring in some substances from outside and which expel some other substances from inside. Such pumps must be the result of a long evolution that preceded the first cells. Nevertheless, any form of life that is not made of cells cannot live free in a fluid like water, but it must be attached to the surface of some suitable rocks, where a flow of nutrients must exist. The most plausible hypotheses about the appearance of life on Earth suppose that before the appearance of cells, life was restricted to pores inside rocks from hydrothermal vents, where a flow of dihydrogen and of alkaline ions could provide the energy, and metallic sulfide minerals could provide the catalysts for organic syntheses.
- notaustinpowers 3y agoThe biggest issue is that life has to perform some sort of chemical process. Any lacking any clear delineation of an inside the life in question and the outside, would make continuous chemical processes impossible. A stray breeze blowing away chemicals would effectively kill life. A "cell" having a barrier would allow that chemical process to happen. Life may not require cells in the way cells on Earth evolved, but they'll require cells of some sort.
- feintruled 3y agoOK, headline is more worrying that it needs to be - makes it sounds like we accidentally killed ALL life on Mars. It's actually referring to possible life in the soil sample the Viking lander poured water on.
- dang 3y agoThanks! As usual, the subtitle contains a cromulent substring that we can use instead. passive aggressive subtitle vs. headline wars ftw
- cromulent 3y agoAhem.
- hedora 3y agoAlso, the part where they heated all (?) the samples before testing sounds more problematic than pouring water on some (especially since parts of mars hit 100% humidity, per the article).
- steno132 3y agoI've said this before and I'll say this again: Space is not a amateur game. I see a lot of young SV types thinking they want to build a deep tech space company. And they can. But it requires a couple years of deep training in of aeronautics and physics before you even know what's going on. Elon for instance spent years studying space on his own before launching SpaceX. Elon's at a different level, but we can at least learn a few things from him and SpaceX.
- justrealist 3y agoI'm not sure what strawman you are talking about, but every space company in SV I have seen has been started by domain experts, mostly aerospace and hardware engineers. There are also a lot of space companies focusing on a narrow niche that doesn't involve rockets — sometimes imagery (Planet, other satellites), sometimes 3D printing, etc. It's not like deep training in aeronautics will make you an expert in 3D printing in space - there's not a 101 guide to the space, it's novel tech.
- mrguyorama 3y agoBuddy elon doesn't even understand basic physics, like classical motion and energy equations. Or do you not remember the time he was talking about "compressed gas thrusters" on Teslas? Such a system would be laughably ineffective and all it takes to understand that is a high school physics equation.
- steeve 3y agoClickbait title fooled me.
- mathstuf 3y agoI remember reading (probably from one of his books) that Sagan's idea for a life-detecting experiment on Mars was never actually sent there (apparently this experiment went instead). IIRC, it was basically to put a sample in a box and just watch it to see if anything changed at all in a way that indicates that some chemical process is happening. Here are some interesting slides I found while trying to figure out what his actual experiment idea involved: https://www.vanderbilt.edu/olli/archive/Life_On_Mars_Session_5.pdf https://www.vanderbilt.edu/olli/archive/Life_On_Mars_Session...
- asdff 3y agoMicroscopy could also be a good route. Microbial life should look pretty distinct from inorganic matter, even if everything in the soil sample were dead by the time it was imaged. As far as I know, we have not sent a microscope up capable of resolving even a large mammalian cell, let alone resolve 1 micron bacteria (if these microbes are even to be similar in size as those on Earth). I suspect the vibrations during launch make it especially challenging to actually get a powerful microscope out to Mars unharmed.
- jiggawatts 3y agoIt's very important to NASA to never send anything to Mars that could definitively rule out the presence of life or water. Something I noticed a few years ago is that NASA publishes a press release every month or so with the title "possible hint of water found on Mars". There are literally thousands of such web pages on their site:https://www.google.com/search?q=site%3Anasa.gov+"hint"+"water"+"mars" https://www.google.com/search?q=site%3Anasa.gov+"hint"+"wate... Nobody ought to be this obsessed with something, unless there's an agenda. It's like cigarette companies going on and on about how their latest product is "more healthy". What's going on is that NASA has had a lot of trouble in recent decades maintaining their funding. There's not a lot in space that excites US senators. There's no oil, no resources that can be practically mined, etc... So they have to have some sort of goal, something they have to get funding for so that they can go "look for it". Some NASA administrator picked "water on Mars". Now it has morphed into a reason for the agency to exist, which means if it was ever shown not to exist, then NASA would face a real existential risk itself. So they'll drag their feet as long as possible, sending every possible instrument they can pack into a rover, except for the one that could definitively rule out life and/or water. This is why they didn't send a microscope, and most likely won't send one on the next mission either.
- zabzonk 3y agoin larry niven's couple of sf stories set on mars, water kills the sentient, but aggressive, martians instantly.
- Bluescreenbuddy 3y ago[flagged]
- zokier 3y ago> As I have argued before, we need a new mission to Mars dedicated primarily to life detection to test this hypothesis and others. It should explore potential habitats on Mars like the Southern Highlands, where life could persist in salt rocks close to the surface And the refutations to the authors original pleas are still as valid as they were then: https://www.liebertpub.com/doi/10.1089/ast.2017.1749 https://www.liebertpub.com/doi/10.1089/ast.2017.1749
- clucas 3y agoOn a quick scan, I'm not seeing anything in your linked article that counters either your selected quote, or the thrust of the OP. Can you help me out by pointing to a section or summarizing the argument?
- zokier 3y ago"It should explore potential habitats on Mars like the Southern Highlands, where life could persist in salt rocks close to the surface" is basically saying that we should throw away planetary protection guidelines in favor of studying places with potential for extant life, an argument that the author has been making repeatedly for a long time, and what the article I linked counters. The discussion about Viking lander results was just build-up for that final paragraph making the argument for new life-searching mission.
- clucas 3y agoI see. The OP article doesn't say anything about throwing away planetary protection guidelines... are you saying that there is no way to do the mission discussed in the article without relaxing or eliminating these guidelines? I feel like I'm wading into the middle of a lover's quarrel, where the words have nothing to do with the actual fight...
- m3kw9 3y agoActually finding life vs is there actually life makes no difference. There is almost zero chance that we only have life here on earth and exponentially high chance the detection method give false positives
- andrewprock 3y agoThis seems a bit hyperbolic. I suppose there is a tiny chance that we caused the extinction of the last vestiges of microscopic life on Mars. I doubt it though. Science is about trying things and learning from our mistakes.
- iraqmtpizza 3y agohow desperate do you have to be to write this headline? endless experiments fail to find life (as any reasonable person would expect) and then you justify your undying belief in extraterrestrials by conjecturing that maybe there was life all along but we killed it accidentally! this is one of the most cringe headlines I've ever read in my entire life. you didn't find life at any point. this is not in dispute. I hope this is actually just brain dead clickbait and not genuine simping for aliens by claiming xenocide based on literally nothing. hey, maybe one of the scientists accidentally farted on all the moon rocks too. we can't rule this out. better alert the media and make it seem like we're actually on the case alien hunters can't get a life here where it's warm so why would they get any out there? the real aliens are truly the friends we made along the way
- IvyMike 3y agoThe article is not claiming xenocide; it is saying that the probe may have killed the life in the sample when it added water. Yes the headline is a little ambiguous, but I assume most readers have built up a filter for that by now.
- iraqmtpizza 3y agowalking through sewage does indeed strengthen the immune system. at least as much as water filters out the weak aliens. there was no life. the only fluid anywhere near the planet surface is a weak amount of carbon dioxide. there are no billion-year-old organisms still alive from when there was liquid water. I've heard of child-like wonder but this is just embarassing. i hope none of my taxes go to this "if elvis is alive, he lives on the moon" is a true statement only because elvis is not alive. if life was in the sample, it was killed by water is a true statement only on the technicality that the premise is impossible. the author either deeply misunderstands propositional logic or it's intentional clickbait. probably both. https://www.wolframalpha.com/input?i=truth+table+%28p+implies+q%29+and+%28%28not+p%29%29 https://www.wolframalpha.com/input?i=truth+table+%28p+implie... https://www.wolframalpha.com/input?i=truth+table+%28p+implies+q%29 https://www.wolframalpha.com/input?i=truth+table+%28p+implie...
- gigatexal 3y ago[flagged]
- perryizgr8 3y agoThe best way to conduct a proper experiment is to either send a human, or a robot that is as adaptable as a human. This will let us run an effective experiment, react to intermediate results and continue based on that. Anything else is a waste of time, we'll never get anything conclusive.