A Primer on Long-Duration Life Support (mceglowski.substack.com)

The article explains why long-duration Mars missions are limited more by life-support systems than by headline-grabbing rocket challenges, focusing on how oxygen, water, air purification, and food must be reliably managed for years with limited mass and space. It describes the trade-offs of recycling—especially water, where pushing toward high closure rates requires multiple heavy, tightly coupled machines—and contrasts earlier “pack-and-forget” approaches with what happens past roughly a month. It also highlights persistent problems like storing nutritious, appetizing room-temperature food for multi-year trips and the engineering and contamination risks of handling human waste.