Research Note: Life Support Turns Days Into Cost
Published May 2026
Question
For uncrewed payloads, mass and trajectory dominate the first calculation. For people, life support changes the shape of the problem. A personal lunar route needs air, water, waste handling, pressure, fire detection, thermal control, redundancy, and repair assumptions before it can claim to be a route.
Source-Backed Data Points
- NASA says ECLSS includes the Water Recovery System, Air Revitalization System, and Oxygen Generation System. Source: NASA ECLSS reference.
- NASA reports that the ISS system achieved a 98% water recovery goal after the Brine Processor Assembly, compared with 93-94% total recovery before it. Source: NASA water recovery milestone.
- NASA's ECLSS reference says the Water Recovery System reclaims wastewater including crew urine, cabin humidity condensate, and water from EVA suit hydration systems. Source: NASA ECLSS reference.
Reading
The ISS water milestone is a useful anchor because it shows the difference between a demonstrated loop and a hoped-for loop. The move from 93-94% to 98% recovery is not just a percentage point story. It reduces the resupply burden for long-duration missions and shows how much hardware discipline sits behind the word "closed."
For a short personal lunar route, closed-loop life support may not always be cheaper than carrying consumables. But the model still needs to price the choice. Open loop means more consumable mass. Closed loop means more hardware, testing, maintenance, and failure handling.
Model Rule
CosmosExplore will treat life support as a duration multiplier. The cost model needs crew days, water recovery assumption, oxygen-generation assumption, consumables reserve, and redundancy level. Without those fields, "one person to the Moon" is not yet a cost model.