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4194Total

4194Open

0Solved

9Humans

We lack closed-loop biological carbon dioxide scrubbers for human spacecraft cabins.

open Global / Unspecified, Global

Chemical lithium-hydroxide canisters are consumable, heavy, and wasteful for multi-year missions. Algae photo-bioreactors capable of converting human exhaled CO2 directly into oxygen and edible protein are required.

climate-environment global-unspecified human lack closed-loop biological carbon dioxide scrubbers spacecraft cabins chemical society-governance solutions long mathematics-logic science-space term

WS02142

By Ian Patel · 2026-07-22T08:00:00Z · Horizon: 2029

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WS02142 | World Solve | https://www.worldsolve.org/index.php?view=problem&id=2142