from the miracle-food-of-high-energy-algae dept.
Arthur T Knackerbracket has processed the following story:
While the world is marveling over the first images and data now coming from NASA's Perseverance rover mission seeking signs of ancient microscopic life on Mars, a team of UNLV scientists is already hard at work on the next step: What if we could one day send humans to the Red Planet?
There's a lot to consider when sending people, though. Human explorers, unlike their rover counterparts, require oxygen and food, for starters. It also takes about six to nine months—both ways—just in travel time. And then there's the air itself. Martian air is roughly 98% carbon dioxide (Earth's is a fraction of 1% for comparison) and the air temperature averages an extremely frigid -81 degrees.
It's these challenges that UNLV geochemist and NASA Mars 2020 team scientist Libby Hausrath and postdoctoral researcher Leena Cycil, a microbial ecologist, are exploring. And a big part of the answer? Algae.
[...] Hausrath and Cycil are among a handful of scientists looking at growing algae under the low-pressure, low-light conditions seen on Mars, and are pursuing different species than previous studies.
Early results are promising. So far, they've identified three species of algae that show substantial growth under extreme conditions. They used a low-pressure vacuum chamber to simulate atmospheric pressures relevant to Mars and topped it with a plate of tempered glass to allow light in at half the sun exposure present on Earth.
[...] Hausrath and Cycil are already working with a NASA engineer on applications for their work. Their study shows these organisms can produce oxygen at levels comparable to what people need to survive, but engineers will be the ones to put that into practice.
Hausrath and Cycil's work is part of preparing for future short-term human exploration of Mars, where astronauts—instead of rovers—will conduct further experiments and gain more knowledge of the planet and its history. Ultimately, these visits will help determine if Mars can support human habitation.
More information: Leena M. Cycil et al, Investigating the Growth of Algae Under Low Atmospheric Pressures for Potential Food and Oxygen Production on Mars, Frontiers in Microbiology (2021). DOI: 10.3389/fmicb.2021.733244
(Score: 3, Interesting) by FatPhil on Tuesday October 25 2022, @11:38PM (13 children)
Without that information, there's no information, as that's the only important information. The fact that it was not made clear implies that it's going to be something completely impractical.
Personally, I reckon they should focus on getting a rover/bot colony up and functioning before sending the bags of mostly water up there. At least that might involve advancing robotics for humans on earth too. Sending humans there first to inevitably die due to lack of one of the essentials for life seems relatively pointless. Then again, there's always the B Ark...
Great minds discuss ideas; average minds discuss events; small minds discuss people; the smallest discuss themselves
(Score: 5, Insightful) by Immerman on Wednesday October 26 2022, @12:31AM (7 children)
Agreed, information lacking key details is no information at all. But it seems like that's becoming increasingly normal in reporting, and not just in science.
If I recall correctly though, pound for pound algae can produces more oxygen than any other plant in the world... but that might just be specific species. They have long been one of the prime candidates for atmospheric bio-recycling.
As for robots - it's a nice idea, as long as you don't mind waiting a few extra centuries to actually get anything done. Consider everything all the Mars rovers have done in recent decades, and the fact that a single human could have done all of it in a few days, maybe a week. And that doesn't even involve any significant manipulation of the environment. Our robots are still woefully limited physically, and AI is still far from being ready to even safely drive down the street on its own. And the communication lag with Mars means we need either strong AI, or the patience to take years to do something that humans could do in days.
So long as the initial outpost is designed to simply deploy and go, with no *need* for local resources, I see no reason we shouldn't send people right away. Other than the fact that the moon would be a much more productive starting point.
(Score: 2) by maxwell demon on Wednesday October 26 2022, @04:44AM (4 children)
I think an AI for driving on Mars should be much easier than street-worthy AI. To start with, there's no significant traffic, no pedestrians, not even animals, so it basically only has to deal with non-moving obstacles; while there may be more than one vehicle, all vehicles in use can communicate their positions directly instead of relying on optical recognition (and those vehicles are likely to be sent in different directions anyway, to cover a greater area). If temporary conditions hamper navigation (e.g. I don't know if Martian sand storms could reduce visibility enough to affect the AI), the rover can just stop moving until the condition is over; cars that stop as soon as there's a bit of rain would be totally unacceptable on the street, of course.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 2) by Freeman on Wednesday October 26 2022, @01:47PM
Yep, good thing self-driving vehicles don't plow into stationary police vehicles. That would be a real problem, then.
Joshua 1:9 "Be strong and of a good courage; be not afraid, neither be thou dismayed: for the Lord thy God is with thee"
(Score: 2) by Immerman on Wednesday October 26 2022, @03:31PM (2 children)
Driving, maybe. How about building an outpost? That was my real point - existing AI can barely handle driving on well-marked roads, it's nowhere close to being ready to do major construction on an alien world filled with unexpected problems, as would be needed to have them build an outpost before we get there.
If we want to start colonizing Mars this century, I don't see any realistic option other than sending people to do the complicated work. Which probably means taking along a good sized inflatable habitat and enough fuel for a return trip. I think about the best we could hope for autonomously in the near term is a "simple" deployable fuel refinery, where the robots just have to drag stuff out flat, and dig up ice to dump in a hopper. Or maybe drag a melt-and-capture unit around the surface of a glacier.
Even those will be a challenge - but such a refinery can probably be delivered as easily as just the needed fuel for the first return trip, and will continue to pay long-term dividends both for further refueling and as general energy storage - big tanks of methane and oxygen can fuel both generators and bioreactors to produce extra electricity and food on demand.
(Score: 2) by maxwell demon on Wednesday October 26 2022, @07:27PM (1 child)
There would be no need for the AI to be completely autonomous. There's still communication between Earth and Mars, just with delay. You can't remote-control a Mars machine, but you can handle unexpected problems on Earth and send new commands or even completely new code to those machines in order to handle those. As long as the AI is able to put itself into a safe resting mode and send the relevant data to Earth once any unexpected problem occurs, and then wait for new instructions from Earth, that's sufficient.
The Tao of math: The numbers you can count are not the real numbers.
(Score: 2) by Immerman on Thursday October 27 2022, @12:55AM
Pretty much impossible to repair a jammed machine with lag between 8 and 50minutes unless "just rock it a bit" is sufficient. Trying to do the equivalent of sending out a bot with a screwdriver to perform a two-minute fix of a simple problem is likely to be a months-long ordeal, if you can pull it off at all.
And when's the last time you heard of *any* construction project going a week without needing any simple fixes?
(Score: 1) by BlueCoffee on Wednesday October 26 2022, @09:37AM (1 child)
Agreed, information lacking key details is no information at all. But it seems like that's becoming increasingly normal in reporting, and not just in science.
Attention grabbing "may/could/might" headline stories about early stage, preliminary, & exploratory scientific "vaporware" are quite prevalent in the media nowadays.
(Score: 2) by Immerman on Thursday October 27 2022, @01:14AM
Still better than the headlines that leave out the qualifiers for the exact same story... but yeah. I do my best to never visit any site with such obvious click-bait headlines.
Well, except this one obviously - gotta rant about them somewhere!
(Score: 3, Informative) by ElizabethGreene on Wednesday October 26 2022, @04:22PM (4 children)
C. vulgaris captured 1.4 g/L/day with 1.3E7 cells/ml in optimal earth conditions. For that you'd need = ~700 liters of culture medium. The cell density in the low pressure cultures were two orders of magnitude lower, so spitball the lower bound at 70000 liters.
I don't see this as a long-term solution, the water loss due to low vapor pressure is too high. It's far easier to pressurize the containers. That said, from an exobiology perspective, it's very interesting that plant-like life could survive and grow under near-ambient Mars conditions.
(Score: 2) by ElizabethGreene on Wednesday October 26 2022, @04:27PM
If I remember the Chinese closed loop life support experiments correctly, I believe they projected 16 square meters of growing area per person. I don't have a citation for that, but I'm 80% confident I'm remembering the number right.
Nasa's NTRS service has an archive of millions of space-related papers. Search it for "Closed loop life support" and I'm sure you'll find it.
(Score: 2) by Immerman on Thursday October 27 2022, @01:22AM (2 children)
What water loss? So long as the environment is sealed (which is has to be to collect the oxygen), all the water will simply condense again - either in the farm, or in the pump pressurizing it for your habitat.
Meanwhile, the extreme low pressure means you don't need any structural supports - you can simply unroll a transparent puncture-proof bag on the surface and add water.
And in the long term, being in a minimally populated, nutrient rich, and heavily irradiated environment should drastically accelerate the evolution of algae batter able to thrive in those conditions. Radiation sucks for larger organisms where it leads to cancers, etc., but when farming single-celled organisms when one dies its just more nutrients for their neighbor, and "malignant" mutations are exactly what you're hoping for.
(Score: 2) by ElizabethGreene on Thursday October 27 2022, @03:34AM (1 child)
The idea here is to generate oxygen and/or fix CO2 under Mars ambient conditions. If you do that in open ponds/swimming pools, you'll have a large amount of water loss due to the low vapor pressure. If, as you suggest, the cultures are sealed in a puncture-proof bag the mass of any appreciable amount of water will necessitate the bag be strong enough to hold an internal pressure significantly higher than Mars ambient.
Elaborating, I don't see (growing algae in ambient pressure ponds) to be a long-term solution (because) the water loss due to low vapor pressure is too high (and the paucity of water on Mars makes that very wasteful). Additionally, it would be a real dick move to contaminate a planet we're searching for life that way. (If the entire function of growing algae on Mars is to harvest Oxygen) It's far easier to pressurize the containers (since that application requires that anyway).
You're right about it being a high mutation environment. UV and cosmic radiation, not replicated in this study, will rapidly select for hardiness and/or wipe out the cultures entirely.
(Score: 2) by Immerman on Thursday October 27 2022, @02:59PM
Open air ponds might be useful for long-term terraforming projects, but not for colonization.
I think you're grossly underestimating the evaporation rates to even consider them. At Mars ambient pressure the boiling point of water is around -68C, 8C below the average surface temperature, and WAY below the highest recorded temperature of +21C. In fact, (pure) liquid water can't even exist at temperatures below ~-22C no matter how high the pressure - in fact liquid water can only exist at pressures above 1kPa (~0.01atm) and temperatures above 0C (phase diagram: https://i.stack.imgur.com/dU84T.png), [imgur.com] so any ponds are going to have to have high solar gain. And probably insulation from the ground if they're not in the tropics.
So yeah, I'm betting hard against the existence of open air ponds on Mars any time in the next few centuries - they're going to have to dramatically increase the temperature and air pressure before liquid water can exist on the surface, and that's a huge terraforming project in itself.
Bags though won't actually need to hold pressure much beyond what naturally accumulates from water's partial pressure at the temperature - and even at a balmy 21C you're still only talking 0.36psi (2.5kPa) (though the presence of oxygen and CO2 will increase that)
The *bottom* of the bag will be subjected to higher water-column pressure - but that pressure will be exactly balanced by the inwards pressure of the ground - the bag only needs to be strong enough to contain the water pressure across the tiny gaps between sand grains - which is trivial.
The actual forces the bottom of the bag will be subjected to are determined by the pressure difference times the unsupported area spanned. Even if the pond is 1m deep, under Mars 38% gravity that translates to only 3.8kPa (plus surface pressure, so lets call it 5kPa) at the bottom, and the outward force exerted on even a big 1cm^2 gap will be only 0.5N (1.8oz). Your average ziplock bag can handle that without trouble.
As for contamination...I agree completely. However, since they didn't ask me, and the drive seems to be for colonization rather than a research outpost, it also looks to be inevitable. We can only hope that Mars life, if there is any, is alien enough that we'll still be able to recognize it living alongside Earth-descended life. Which frankly seems unlikely without extreme effort - microbes tend to lean hard into "form follows function", and I don't imagine any Mars life will have a lot of deeply alien functions. I suppose looking for amino acids other than the 20 life used on Earth might do it. Of course, if Mars life is actually related to Earth life (i.e. panspermia happened) it'll likely be all but impossible to discover that for sure.
(Score: 2) by fliptop on Wednesday October 26 2022, @11:01PM (1 child)
And his results are certainly interesting [youtube.com]. This idea reminds me of the slimy swill they ate in the Matrix. Not sure I'd be a huge fan of that...
To be oneself, and unafraid whether right or wrong, is more admirable than the easy cowardice of surrender to conformity
(Score: 2) by Immerman on Thursday October 27 2022, @03:09PM
Texture is a choice. If you have algae you can make algae flour, and with it at *least* unleavened bread (and gravy!).
Some mat algae makes a decent vegetable as is, but mat algae is also harder to farm than the free-floating varieties. I think just because the strings tend to tangle and clog machinery, which can be dealt with, but is an added complication.