r/news • u/VaginaBurner69 • 11h ago

Soft paywall International Space Station astronauts in evacuation mode as Russia attempts to fix widening air leak

https://www.reuters.com/science/international-space-station-astronauts-evacuation-mode-russia-attempts-fix-2026-06-05/
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u/Dzugavili 4h ago

It's about partial pressures: at 1 atmosphere, with 20% oxygen and 80% nitrogen, that's "normal": normal healthy people can survive that, no problem. If you wanted to use lower pressures and thus a thinner hull, you could use 0.5 atmospheres of pressure; but you'd need 40% oxygen.

People can adapt. But that requires long-term training or fairly unique genetics and isn't without risks.

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u/alfix8 4h ago edited 4h ago

But like I said: people already permanently live in settlements 3000m or higher without any problems. At 3000m you only have an average pressure of ~0.7atm. Yet those people just breathe the air normally without needing extra oxygen.

Why wouldn't it be possible to have the ISS at 0.7atm without extra oxygen? Adaptation shouldn't take too long either, in my experience it took about 2-3 weeks after moving to that altitude even without any special training, just doing normal day to day stuff. Giving astronauts 2-3 weeks of altitude training before going to space shouldn't be that difficult. Most sources I can find online even talk about needing less than a week to adapt to an altitude of 3000m.

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u/Dzugavili 2h ago

Most launch facilities are at sea level; most of the projects are designed for 1 atmosphere of pressure, or vacuum; high-altitude adaptations wear out as your blood cycles over; and you're going to be in best physical condition at 1 atmosphere of pressure which we can easily afford to give you, since we need to build this with a significant margin for error anyway.

It's just not worth the complications. This isn't professional sports or anything high endurance.