Is it possible for suitably beefed-up multicellular life to survive on the Martian surface and to harness incoming solar radiation via photosynthesis to supply a food chain, and thus support an ecosystem? Or could this possibly even be done underground?
Quote from: sanman on 09/21/2016 12:21 pmIs it possible for suitably beefed-up multicellular life to survive on the Martian surface and to harness incoming solar radiation via photosynthesis to supply a food chain, and thus support an ecosystem? Or could this possibly even be done underground?Just skip the intermediate steps, just genetic engineering to create humans with green skin and they can use photosynthesis to produce food.Really, you don't need to ask if any new technology is applicable to spaceflight
Wow, I just recently registered here at NSF (though I've followed the field avidly for many years), but as a wetware engineer myself, did not expect to have much to say here among the actual rocket scientists!. I try to RTFA the peer-reviewed article (http://www.nature.com/articles/ncomms12808) itself before commenting, which I finally had a chance to do yesterday. The answer to your question hinges on what you mean by "possible". No, right now we could not create a multicellular creature that could "thrive" on the Martian surface, but it is a reasonably conservative prediction that this will be "possible" on the timescale where humans might get there (decades). The basic insight I think was first popularized by the physicist, Freeman Dyson, making the point that one could in principle engineer an organism where energy collection and metabolism can be spatially separated, with a vacuum and radiation-hardened light-collector at the surface connected by stem-and-roots to a sub-surface body that melts water and collects nutrients (a space plant). I am not finding his original paper, but he discusses the idea in an Atlantic article (http://www.theatlantic.com/past/docs/issues/97nov/space.htm). When I cloned my first gene in the '80's, it was still a big deal to engineer small viruses (my field) but now Craig Venter's group has synthesized whole bacterial genomes from scratch (a thousand-fold larger), so Dyson's ideas are not that far off. In the case of the Tardigrade paper, this organism has multiple mechanisms making it very tolerant to extreme conditions, but relevant to NSF, they show that just one gene that binds to and protects DNA from radiation damage can confer upon human cells in culture substantial resistance to radiation. Given recent progress in precise gene-engineering, it is not at all far-feteched that by the time humans are going to Mars in significant numbers, we will be arguing over not the possibility, but the bioethics of engineering colonists to be better adapted to their new home.
How to get the point of self-sustainability? Could a self-sustaining eco-system under Mars ambient conditions be even remotely possible?
In the short term (10-20 yr), it is almost certainly going to be easier to use conventional engineering (mirrors, fiber-optics, drilling and dredging equipment) to bring Martian light/heat energy, water ice, carbon/oxygen/nitrogen/etc., together in some relatively protected subsurface space and then let genetically engineered biology do the complex biochemistry to get the stuff you want (O2, water, food, structural materials, etc.). Enough is known at least about the surface materials on Mars that one could start now engineering organisms to do this using simulated Martian "soil" here on Earth. The chemistry is pretty harsh, but Terrestrial extremophiles have taught us that Life can adapt amazingly far, to a first pass wherever liquid water is possible. Getting Planetary Protection approval to use this on Mars is of course a whole 'nother story.
Some researchers have developed a way for electronics to control bacterial gene expression:http://wallstreetpit.com/112807-powerful-genetic-engineering-technique-bodies-talk-electronics/So I'm wondering what the possible applications might be on Mars. I was thinking that in the case of ISRU, you could electronically signal your bacteria which metabolic pathway to use, depending on what type of raw materials are available. Maybe you could have some electronically-controlled bio-reactor which does this. Instead of having to select which bacteria are right for the situation, you could have a single type of bacteria which was like a swiss army knife, whose specific capabilities could be selectively activated by electronics.
Don’t let a tardigrade’s size fool you: they may be only 0.05 inches at most, but they are the most resilient life form known to humans. Despite being aquatic, they can live for over 30 years without water or even food; they have been known to survive through temperatures well above 200 degrees Fahrenheit and close to absolute zero (minus 460 degrees Fahrenheit); they can withstand high pressure, strong radiation and even the vacuum of outer space.
Perhaps if this resilience could be built into other proteins, it might allow for engineering/cultivation of more lifeforms which could be adapted to Mars conditions.
Those Himalayan/Arctic lichens that you mention are still just naturally adapted to Earth conditions. No attempt has been made to try to artificially adapt them to even more extreme conditions not found on Earth. Who knows - maybe life can be made that adaptable.
Meanwhile, here's an article about possibly adapting the human body for better survival characteristics on Mars or in space:http://gizmodo.com/will-humans-have-to-upgrade-their-bodies-to-survive-on-1793236286
Quote from: sanman on 03/17/2017 10:58 pmThose Himalayan/Arctic lichens that you mention are still just naturally adapted to Earth conditions. No attempt has been made to try to artificially adapt them to even more extreme conditions not found on Earth. Who knows - maybe life can be made that adaptable.Earth life can be only adapted so far. There is no way around the need for a minimum temperature for any appreciable metabolic rate. To have an in any way useful metabolic rate you need to at least raise ambient temperature.{snip}
Mammals solved that problem by going warm blood. If we can surround the creature by an insulating layer, possibly a near vacuum, it may have an internal temperature of say 10 degrees centigrade.
Micro life can adapt to Mars conditions. In tests some arctic lichen were able to metabolize and even grow somewhat. But metabolic growth would be way too small to be useful.
Quote from: guckyfan on 09/29/2016 06:02 pmMicro life can adapt to Mars conditions. In tests some arctic lichen were able to metabolize and even grow somewhat. But metabolic growth would be way too small to be useful. This may be what guckyfan was referring to: http://www.planetary.org/blogs/guest-blogs/20120515-earth-life-survive-mars.html