The Guardian reported yesterday on 'The Lunar Hatch' project, which is aiming to send fertilised sea bass eggs into space, so they can farm fish for astronauts.
Lunar Hatch’s ultimate aim is to create a “closed-loop food chain” on the moon, using a series of compartments. The first tanks will be filled with water from ice found at the bottom of craters at the moon’s poles. The wastewater produced by fish in these tanks will be used to produce micro-algae that can then be used to feed filtering organisms, including bivalves, or zooplankton would collect some of the waste.
The faeces from the sea bass in the first tank would, meanwhile, be treated by shrimps and worms that would in turn be food for the fish.
“The aim of Lunar Hatch is to have no waste,” Przybyla [the researcher leading the project] says. “Everything is recycled through an aquaculture system that would have to be autonomous for four to five months.”
The team has calculated that to provide two portions of fish each week for seven astronauts on a mission lasting 16 weeks, about 200 sea bass would be needed. As well as the 200 fertilised sea bass eggs sent into space, another 200 siblings produced by the fish at Palavas-les-Flots will be kept as a control group.
Below is the abstract of a journal article by Przybyla, discussing the prospects and practicalities of space aquaculture.
The presence of a human community on the Moon or on Mars for long-term residence would require setting up a production unit allowing partial or total food autonomy. One of the major objectives of a bioregenerative life-support system is to provide food sources for crewed missions using in situ resources and converting these into the food necessary to sustain life in space. The nutritive quality of aquatic organisms makes them prospective candidates to supplement the nutrients supplied by photosynthetic organisms already studied in the context of space missions. To this end, it is relevant to study the potential of fish to be the first vertebrate reared in the framework of space agriculture. This article investigates the prospects of space aquaculture through an overview of the principal space missions involving fish in low orbit and a detailed presentation of the results to date of the Lunar Hatch program, which is studying the possibility of space aquaculture. A promising avenue is recirculating aquaculture systems and integrated multi-trophic aquaculture, which recycles fish waste to convert it into food. In this sense, the development and application of space aquaculture shares the same objectives with sustainable aquaculture on Earth, and thus could indirectly participate in the preservation of our planet.
Notably, the article suggests that space aquaculture is important because a 1994 study of astronauts' physical performance found that "an increase in carbohydrates (from plants) and a decrease in animal protein and fat can disturb the diet balance".
I'm not a nutritionist, but I'm a little wary of this claim. The study was ground-based, only studied 12 women, and found "physical performance and LBM [lean body mean] can be maintained under normal gravity conditions in active women who consume a Space Shuttle food-system diet for 28 days". We've made big strides in vegan nutrition studies over the last 30 years, and I don't think this study is enough to justify an investment in space aquaculture.
Ultimately, I'm very worried about space aquaculture because exporting our exploitation of non-human animals to Mars or the Moon means taking speciesism to the stars. We shouldn't risk locking in such harmful values. Farming fish, shrimp and worms in space means increasing the scale at which we farm animals who must be farmed in large numbers, for whom we know little about optimal welfare conditions, and for whom it might be especially challenging to galvanise public sympathy.
Relatedly, you might be concerned about directed panspermia: attempts to deliberately foster animal life on other planets. I understand at least one company is trying to do this.
This seems largely theoretical today but if you think advances in space exploration are coming soon (whether that's due to increased investment from private companies, or the arrival of transformative AI), this issue might become dangerously real quite quickly. Working on space governance for animals might be an animal welfare intervention that's robust if you have short timelines.
Thanks for sharing, though I have to say I'm a little sceptical of this line of thought.
If we're considering our Solar System, I expect almost all aquaculture (and other animal farming) to remain on Earth compared to other planets, indefinitely.
In the short-run this is because I expect at all self-sustaining settlements inhabited by humans beyond Earth to be very difficult and kind of pointless. Every last gram of payload will have to be justified, and water will be scarce and valuable. If there are any more calorie-efficient ways to grow or make food, compared to farming animals, then at least initially I don't see how there would be animal farming.
And then if (say) a city on Mars really does become advanced enough to justify animal farming, I would expect at that point we'd have bioreactors to grow the animal product directly, without the energy wastage of movement, metabolism, and growing a brain and other discarded organs.[1]
I also think this applies to the very long-run, beyond our Solar System. I personally struggle to picture a civilisation advanced enough to settle new stars, but primitive enough to choose to raise and slaughter animals. Not even “primitive” in a moral sense; more like technologically inept in this very specific way!
I also think there needs to be a specific mechanism of lock-in, in order to think that the decision to farm animals off-Earth (or deliberately choosing not to) should strongly influence long-run treatment of animals. I'd expect the more important factor is humanity's general attitudes to and treatment of animals.
I do buy that there would be something symbolically significant about the relevant actors explicitly choosing not to farm animals off-Earth, though, that could resonate a lot (including for animal conditions back on Earth).
(This comment might also be partly relevant)
Honestly I think it's notable how many startups and even academic projects get funding based on claims that they're building some component of a mission to Mars or the Moon, based on assumptions which strike me as completely wild and basically made-up.