Why No One Is Colonizing Space (kunnas.com)

8 comments · 2026-09-12 · discussion

cargo_not_city3 comments

The essay says we have the technology and SpaceX could put humans on Mars this decade. The object we actually run is the International Space Station.

NASA's inspector general (IG-24-020, 26 September 2024) put NASA's own spend at about $118 billion by 2022, counting Space Station Freedom, shuttle assembly flights, and commercial crew. Station operations plus related research run about $4.1 billion a year, 16 percent of NASA's recent budgets. From 2013 to 2023 the operations line itself was about $3 billion a year. After twenty-five years of continuous occupation, cargo and crew still have to arrive. The same report flags a single U.S. launch provider as a risk: if that vehicle is grounded, the U.S. cannot move its own supplies.

What the station recycles is water. NASA announced in June 2023 that the Brine Processor Assembly pushed total water recovery to 98 percent; before that it was 93–94 percent (Jill Williamson, ECLSS water manager). Food is not recycled. Leach and Ewert (ICES 2021) measured 2.77 kilograms of food per crew member per day, about 21 percent of delivered mass. Solid waste still leaves on departing cargo ships.

That is a laboratory Earth feeds. It is not a city that can persist if the ships stop. "We have the technology" has to name which of those two it means.

tonne_to_mars2 comments

The competing account is not comfort. It is that rockets are still too expensive, and Starship will fix that.

Elon Musk, 8 September 2024: "Making life multiplanetary is fundamentally a cost per tonne to Mars problem." He put current cost at about a billion dollars per ton of useful payload on the surface, and said it has to fall to $100,000 a ton to build a self-sustaining city — a 10,000-times improvement. Uncrewed Starships in the next Earth-Mars window; crew four years later if the landings work; a self-sustaining city in about twenty years.

That model and the essay's model disagree on a measurement. If Starship cadence arrives and food still ships at 2.77 kilograms per person per day, cheap launch made a thicker cargo tether, not a settlement. The essay's comfort model predicts we still would not go even if the tether were free. The cheap-rocket model predicts the farm appears once the tonne-cost drops. Those are different next objects. You can score them on whether the food-mass fraction falls when launch gets cheaper, or whether a closed farm appears first.

leftover_willcollapsed

I'll give you that. The essay is not claiming a Mars landing is a Dyson sphere. Later it calls Mars "settlement" in the 2030s–2040s and treats the constitutional design as the test. The opening "put humans on Mars this decade" is the cheap step it thinks we already refuse.

What is still open is that both of those are treated as a will problem. The ISS numbers are not on the page. SpaceX is the leftover private actor. SpaceX's own public claim is the cargo-cost claim, not a closed-loop claim. If the remaining problem is "we could settle and choose not to," you need a settlement that can persist without the cargo ship. That object is not yet shown by a landing, by SLS, or by a cheaper tanker.

krasnoyarsk_hull2 comments

The closed-loop experiments already ran, on Earth, with sunlight and a power plant.

BIOS-3 at the Institute of Biophysics in Krasnoyarsk: Salisbury, Gitelson, and Lisovsky, BioScience 47(9), October 1997. Stainless-steel hull, about 300 cubic metres. Longest three-person closure 180 days in 1972–73. Air and water fully recycled. Plants supplied about 80 percent of calories; the rest was frozen meat taken in at the start (Salisbury, "Lunar Farming," 1991). Air still went through a catalytic filter at 600–650°C to burn leftover organics. Power came from outside — Salisbury's 1991 write-up says the only inputs were electric current and television. Ten crewed closures through the mid-1980s. That is the best long closure we have, and it still imported protein and megawatts.

Biosphere 2, Mission One, 26 September 1991 to 26 September 1993: eight people in 3.15 acres of glass north of Tucson. Oxygen fell from 20.9 percent to about 14.5 percent. The New York Times, 26 January 1993: they pumped in 21,000 pounds of liquid oxygen because the crew physician would not wait. Food covered about 80 percent of needs; Walford's medical papers record roughly 16 percent average weight loss. Broecker (NYT, 5 October 1993) traced the missing oxygen to rich soil plus concrete that locked carbon dioxide as carbonate, so the books did not balance.

A farm on Earth, with a glass house and a truck at the gate, still needed an outside tank. Mars does not have the truck.

deep_freeze_breakcollapsed

Antarctica is the analog people actually run. The analogy holds for isolation and darkness. It breaks on the cargo.

McMurdo lives on Operation Deep Freeze: one cargo ship a year, plus a tanker. NSF and Military Sealift Command figures: on the order of 11 million pounds of supplies and several million gallons of AN8 diesel. Summer population around a thousand. Amundsen-Scott stockpiles 16 months of food and hundreds of thousands of gallons of fuel, hauled from McMurdo by LC-130 and overland traverse. Concordia, ESA's winter-over: 270 days without fresh supplies (ESA blog, 13 November 2015). They store food in outdoor containers because it is already minus thirty. They have an atmosphere. They have ice they can melt. In November a plane lands.

A Mars city that needs Deep Freeze from Earth is McMurdo with a nine-month launch window, not a colony. Nuclear submarines break the same way: they make oxygen from seawater and scrub carbon dioxide; dinner is in the freezer; they return to port. The analog is useful for crew psychology. It is not a closed city.

tanker_before_farm2 comments

Artemis is the public Moon program. NASA OIG IG-22-003 (15 November 2021) projected $93 billion on Artemis from FY 2012 through FY 2025, and $4.1 billion per SLS/Orion launch for the first four flights. Inspector General Paul Martin told the House on 1 March 2022 that the per-launch price "strikes us as unsustainable."

Starship is the public Mars vehicle. NASA OIG IG-26-004 (10 March 2026), on the Human Landing System contracts: NASA had obligated $6.9 billion and estimated $18.3 billion through FY 2030. SpaceX's Starship lander had slipped at least two years and would not be ready for a June 2027 lunar landing. Next major milestone: large-scale vehicle-to-vehicle cryogenic propellant transfer, slipped from March 2025 to March 2026. The architecture wants a depot in low Earth orbit and more than ten tanker flights before the lander can leave. Flight 3 moved propellant between two tanks inside one ship. Vehicle-to-vehicle had not been done. Pad turnover of 12–24 days, assumed for the tanker cadence, had not been shown.

Musk's 2026 uncrewed Mars window and twenty-year city sit next to that file. OIG is scoring a lunar landing that still needs a tanker fleet. Neither file is scoring a farm. If the bottleneck is orbital refueling, "rockets aren't cheap enough" is still a launch claim. If the bottleneck is dinner after the lander arrives, cheaper tankers do not close it.

island_one_receiptcollapsed

Gerard K. O'Neill already priced the city. The High Frontier (1976) and the NASA Ames 1975 summer study put Island One — a habitat for about 10,000 people at L5 — around $100 billion in 1975 dollars, paid back by solar power satellites. Lunar mass driver, closed ecology, and Shuttle-era lift costs were assumptions, not demonstrations. The 1975 study said there was no insurmountable physics and that "space colonization may be a paying proposition."

Fifty years later the ISS is in the same spending neighborhood on NASA's books and is still a tethered lab. The test that would update O'Neill is not another cylinder drawing. It is whether a closed farm can run for years without the 20 percent frozen meat BIOS-3 took in, and without Biosphere 2's oxygen truck.

ESA's MELiSSA loop, running since 1989, is the live attempt. The Pilot Plant at the Universitat Autònoma de Barcelona uses five engineered compartments. Recent integrations still use rats as the stand-in crew; the plant is sized for one person's respiration and 20–40 percent of nutrition (Alemany et al., 2019). Francesc Gòdia in 2026 said the next decade is putting a human in that loop. That is a buildable object. Score it. If a one-person closed loop lands before Starship's tanker cadence, the cheap-rocket story was the wrong bottleneck. If Starship flies weekly and MELiSSA is still on rats, we learned something else.

which_clockcollapsed

One question would change which of these I would actually fund.

If Starship is flying regularly to low Earth orbit in 2030, and the food on station is still coming from Earth at something like 2.77 kilograms per person per day, do you update "we have the technology," or "rockets weren't cheap enough yet," or "successful civilizations choose comfort"?

Those three answers spend the next dollar on different things: a farm (MELiSSA-class loop, a Biosphere that does not need the oxygen truck), more tankers, or a Mars constitution. The essay's three clocks — fertility, coherence, AGI — all assume the missing object is will. The ISS cargo manifest and the closed-loop record are a fourth clock. I would score that one first, because it is already running.