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Could an artificial plant species be designed and created that lives in a vacuum - for example on the surface of our moon?

The main problems I can see immediately would be the lack of an atmosphere for respiration, the lack of microbes in the soil, and the massive temperature swings. Would it be possible to biologically engineer something able to survive and reproduce in those circumstances though?

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  • $\begingroup$ Didn't they find some sort of mold on the previous space station existing in vacuum? I seem to recall seeing people wondering if any of it would survive the re-entry of the Mir. $\endgroup$ – Brad Feb 24 '15 at 21:17
  • $\begingroup$ Don't forget all of the unshielded UV radiation. They'll need more than a little sunlight to photosynthesize. But without ozone to filter out most of the harmful ionizing UV radiation, the sunlight itself is harmful to the plant. $\endgroup$ – cowlinator Jan 15 at 1:27
  • $\begingroup$ @cowlinator Yes, it would need to be uv-tolerant. I don't see that being the hardest part of the problem though. $\endgroup$ – Tim B Jan 28 at 18:26
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There's an Orion's Arm article about this, which lists the various challenges faced by plants in vacuum and the ways in which these could hypothetically be solved. It's not exhaustive and I've added some of my own comments:

  • Extreme temperatures, both hot and cold. These could be solved by variable albedo (the plant being able to change its reflectivity so it reflects more light during the day), high thermal mass (a bigger plant heats up and cools down more slowly), geothermal heat exchange (the aboveground parts of the plant are kept at constant temperature by circulating sap from the belowground parts, since temperature is more stable belowground) and freezing tolerance (the plant can survive freezing in the cold night and thaw out in the morning).
  • Lack of liquid water; water can't even exist as a liquid in a vacuum, but water is essential for plants. Water would need to be provided in vacuum-stable forms such as hydrated minerals (some real-life plants can use water from minerals) or ice underneath an insulating layer of soil.
  • No CO2 or O2 uptake from the atmosphere, since there isn't an atmosphere. Plants need CO2 for photosynthesis and they also need O2 for respiration. The Orion's Arm article doesn't give any solutions for this. Presumably, a plant in vacuum would need to somehow gain these substances from the soil it's grown in. Another implication of this is that plants would no longer need stomata, since stomata are used for exchanging gases with the atmosphere.
  • No wind or animals to assist pollination and seed dispersal. Without these, plants would need to use gaseous or mechanical methods to spread their pollen and seeds, or reproduce vegetatively (e.g. by sending out runners).
  • Elevated radiation, since there's no ozone layer to stop UV and no atmosphere or magnetosphere to stop particle radiation. The article doesn't really mention this, but a vacuum plant would need high radioresistance in order to survive, grow and reproduce.

One thing to take away from this is that most of a vacuum plant's biomass will probably be underground, where it's relatively safe from these challenges. The only aboveground parts would be the leaves and possibly the reproductive organs.

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  • $\begingroup$ it could also reflect the light to the l"eaves" for more photosynthesis power, and having some ideas from ansewers below, such as mine, pavel janicek's and michael richardson's $\endgroup$ – Dexyan Jan 14 at 19:39
  • $\begingroup$ stomata would penetrate the bubbles of oxygen/carbon dioxide for the reactions $\endgroup$ – Dexyan Jan 14 at 19:44
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1.: You need water - Fun fact. First "plants" on Earth started in atmosphere without any oxygen. But without water (Moon soil) you would be no go with even the most clever design ever.

2.: You need minerals - You can go away with microbes, but the plant needs to feed on something. That is how we grow most vegetables for mass production: Hydroponic planting in water enriched by all minerals what plant needs. So again, water only is not enough. Water with minerals could be a GO, but:

3.: You need stable environment. Although you could avoid a loads by clever DNA design of such plant, still, on Earth you have temperature range from -80 Celsius to +50 degree Celsius. I believe that on surface of Moon you can go more extreme ranges.

Long story short: It is engineering problem:

You need plant of a design which would keep its own micro-atmosphere (sphere like design, where plant would breathe inside such sphere)

You need a plant able to survive extreme temperatures both ways. Basically taiga wood mixed with desert cactus.

And, bonus, such plant should survive with as little water as possible (more cactus design than Siberian taiga wood)

In sci-fi setup of really developed DNA engineering, I think you could pass such idea on. But in reality I think you would crash on extreme setup of the environment.

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    $\begingroup$ To expand on this, plants also need pressure if they lived on the surface of the moon, they would probably die from that too. $\endgroup$ – JDSweetBeat Feb 23 '15 at 13:59
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Plants which perform photosynthesis require carbon-dioxide to grow. The metabolism of plants converts CO2 into carbon and oxygen through photosynthesis. The carbon is the main element a plant is made of. Without a carbon-dioxide atmosphere, a plant can not grow.

However, you might be able to grow mushrooms in vacuum. Fungi don't perform photosynthesis. Instead they absorb organic compounds which are or were part of other plants or animals. That means they technically do not need an atmosphere. But you will have to provide a source of nutrients. Fortunately fungi are surprisingly versatile. According to Wikipedia:

Fungi have evolved a high degree of metabolic versatility that allows them to use a diverse range of organic substrates for growth, including simple compounds such as nitrate, ammonia, acetate, or ethanol.

Many of these simple compounds have been detected in nebula, so finding a natural source of them in space isn't far-fetched.

I am not a biologist, but I doubt that you will find a fungi species on earth which grows well in vacuum because their cells evolved to be stable within 100 kPa atmospheric pressure. But you might be able to create one through genetic engineering or, when you have the time, artificial selection (create cultures, lower pressure until most of them die, wait until they regrow, lower pressure further).

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A plant like bamboo? Very unlikely, however, if we go small you might make it happen. Lichen and moss might be able to be designed for such a thing. I know lichen isn't a 'plant' but algae will make chlorophyll.

Things that hug the ground would have a better chance of surviving, just look at would lichen can be found here on earth, they can live in some very inhospitable places. They might be able to hold a small atmosphere and break down the rocks and other minerals and it could handle going into stasis every time the moon turns away from the sun.

So I would expect we would start by playing with Lichen then maybe move on to mosses and go from there

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I would picture this "plant" as appearing as the trunk of a Baobab. Any branches would be very short and may not even exist. Its appearance may be more similar in shape to a saguaro cactus rather than a tree. Any leaves (needles?) would be more photo-voltaic solar cells rather than being chlorophyll-based. The interior of the (water-tight, air-tight, vacuum-proof) trunk would be stocked with water, minerals, and gases that the tree would consume to live and grow.

I would assume that the purpose of such a plant would be to use specialty roots to slowly process dirt and rocks into usable materials. Resupply runs would be needed to replenish its stockpiles and to harvest anything useful it produced.

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you could make the plant have some air scacs, which contain oxygen, for some aerobic respiration, and some CO2, as for photosynthesis, you could modify it so it needs the same amount of O2 as CO2 theese sacs could be either in all leaves, some specialized leaves, directly around the plant's trunk, or others, but the plant still needs some minerals, even if it could get them, like epiphates, from the air which has far less nutrients than the soil, there are no nutrients in a vacuum, but in the moon, i think you could find them (also the reusal of those nutrients is possible)

edit: please look at my comment, it gives good information too

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  • $\begingroup$ You're describing a perpetual motion machine in plant form. The carbon that plants use for growth is drawn from carbon dioxide, not just the sugars they use in aerobic respiration. This is why plants can "lock" atmospheric carbon. Unless new carbon dioxide were added to the system, your air sacs plant could not grow. $\endgroup$ – jdunlop Jan 14 at 22:46
  • $\begingroup$ @jdunlop you forgot that the plant has soil, from there, it could get more nutrients, it is not a perpetual machine, as the plant is not drectly in a vcuum, but in moon soil, the vacuum is of oxygen, as there is non there you could get the needed nutrients for the plant also, it could be a variety of plants with different jobs, such as mycelia and fungi, plus lichen and mushrooms, theese last ones reuse as much as they can, and get nutrients to different plants, and you could bring specialized bacteria for chemosynthesis $\endgroup$ – Dexyan Jan 15 at 10:33

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