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All equipment designed for landing on Mars in the modern era is extensively sterilized. The concern is that given what we've learned about microorganisms in sp
by mapt 11y ago
All equipment designed for landing on Mars in the modern era is extensively sterilized.
The concern is that given what we've learned about microorganisms in space, this may not be enough; "Extensively sterilized" is never "Perfectly sterilized", at least, not without building it out of solid metal and annealing it in space. There was also a last-minute variance granted to the drill bit on Curiosity, which was contaminated between sterilization and launch by briefly opening the box in a lower-spec clean room.
http://www.space.com/13783-nasa-msl-curiosity-mars-rover-planetary-protection.html http://www.space.com/13783-nasa-msl-curiosity-mars-rover-pla...
As we enter an era of inexpensive launch capacity, the sterilization step is actually so expensive it may exceed the cost of the launch vehicle. There is a case to be made for dropping these protections: They're a barrier in the way of a widespread robotic exploration mission, and a manned mission is going to be implicitly contaminative, since you can't run humans through an autoclave. The most conservative route to detecting life before sending humans is years and years of robotic launches to a variety of regions, with several sample returns. It's arguable, but I'm not sure we have the stomach to do that before the 2030's, there's no sign of the major expansion of NASA funding that would be required for the decade of exponentially escalating robotic precursors to a human mission, on the horizon. Given that we're apparently not going to protect Mars from life, that brings into question why we should bother pretending that's what we're doing today. There have already been substantial transfers on previous landers and impactors.
- Symmetry 11y agoThere have certainly been metioroids starting on Mars that made it to Earth without being sterilized[1]. Now, Earth does have a deeper gravity well which might make a difference but Earth microbes have had geological epochs to make the trip to Mars wheres you'd only expect a meteoroid to remain recognizable on Earth's surface for that long in comparison. So I figure that if contamination of Mars by Earth life was a problem it would have happened by the Paleozoic. [1]https://en.wikipedia.org/wiki/Allan_Hills_84001 https://en.wikipedia.org/wiki/Allan_Hills_84001
- david_shaw 11y agoThat makes sense, but wouldn't it be reasonable to assume that there's a major difference between natural seeding of life on other planets via meteors, and humans bringing it over while trying to find natural life? Furthermore, what if life on Mars were fragile enough that Earthly microscopic organisms destroyed it?
- WalterBright 11y agoAt some point we'll either have to either stop worrying about life on Mars being hidden under a rock somewhere or forever put a "humans keep out" sign on Mars.
- trose 11y agoI'm kinda of this thought process as well. If there are hospitable conditions there and we haven't found microbes after a while, I think we should just start dumping tons of them over there. We need something to put some atmosphere there for us. Algae seems to be a really good bet.
- WalterBright 11y agoAnd suppose we do find some biological slime there? Does that then make Mars off limits to all of humanity for all time?
- deleted 11y ago[deleted]
- bdamm 11y agoIt's time for us to accept that we implicitly modify everything we touch. Prime directive needs to have some detectability metric by which we decide it's OK for us to go gangbusters. If the native martian amoebas cannot survive with us present then they lose the evolution race, sorry. Besides, if there are primitive life forms on Mars, it's quite presumptuous of us to assume we could so easily wipe them out.
- Havoc 11y agoWhat is the real contamination risk though? Suppose some biological particle makes it to mars. Then we pick it up, discover that its very dead already, DNA sequence it and find that it matches the common flu. Write it off as contamination, rinse & repeat until we find something that is alive & looks like green men. Or can science genuinely not distinguish earth contaminants vs alien life?
- mattmanser 11y agoI know little about this stuff, but my impression is that there are so many different variations of life and also so many variations that can live in the most bizarre conditions, that we haven't even scratched the surface of classifying them all. Something could survive the trip, grow, be found and still be entirely unknown to us. And it probably wouldn't be all that unlikely. Take this study, that swabbed people's belly buttons and found thousands of unknown bacteria, bacteria only found before in foreign countries the person had never visited and "extremophile bacteria that typically thrive in ice caps and thermal vents" http://www.theatlantic.com/health/archive/2012/12/1-458-bacteria-species-new-to-science-found-in-our-belly-buttons/266360/ http://www.theatlantic.com/health/archive/2012/12/1-458-bact...
- bglazer 11y agoOne possibility, perhaps very unlikely and perhaps somewhat likely, is that Earth life could actually survive and adapt to Martian conditions and subsequently destroy existing Martian life. That seems almost comically improbable, but given that we've found that lichen can survive in the vacuum of space for a year and a half [1] and the mere existence of life on hydrothermal vents and inside Chernobyl[2], I think we can safely say that life is surprising. [1] http://www.astrobio.net/topic/origins/extreme-life/lichen-orbit/ http://www.astrobio.net/topic/origins/extreme-life/lichen-or... [2] http://web.archive.org/web/20080424001002/http://www.sciencenews.org/articles/20070526/fob5.asp http://web.archive.org/web/20080424001002/http://www.science...
- duncan_bayne 11y agoSo, if we accidentally terraform a planet with only microbial life, what's the downside? The only loss I can see is the lost opportunity to study a truly alien ecosystem in detail, but if we can't study it without fatally contaminating it, that was never really a benefit we could enjoy anyway.