Living on the International Space Station means experiencing fifteen dawns every single day

Space · Published 11 October 2026 Swipe more like this →

In short: In orbit, the concept of a day becomes abstract. As the International Space Station speeds around the world, astronauts witness fifteen sunrises every 24 hours. To avoid permanent jet lag, crews must strictly follow fixed schedules that respect the ancient circadian rhythms hard-wired into the human brain.

Maintaining a biological rhythm is a significant challenge in low Earth orbit. While the station's rapid velocity creates a constant cycle of light and darkness, humans are evolutionarily conditioned to a 24-hour cycle. To prevent a state of permanent jet lag, astronauts on the International Space Station (ISS) adhere to fixed schedules for work and sleep that match these ancient rhythms.

Sleep in microgravity requires careful preparation. Most astronauts must hook their sleeping bags to a wall to prevent drifting. Selecting a sleep spot is critical; it must be positioned near a ventilator fan. Because warm air fails to ascend in orbit, inadequate airflow can trap an astronaut within a pocket of their own exhaled carbon dioxide, which might cause oxygen deprivation and a severe headache upon waking.

The environment is far from silent. The constant operation of life-support systems, fans, and air filters creates a persistent background noise that some astronauts compare to living inside a giant vacuum cleaner. While some crew members use earplugs to manage the noise, many eventually acclimatize to the sound, finding the mechanical hum of the systems dedicated to their survival to be strangely reassuring.

Beyond the physical mechanics of survival, the ISS serves as a vital educational platform. During Expedition 38, NASA astronauts Mike Hopkins and Rick Mastracchio, alongside JAXA's Koichi Wakata, engaged in in-flight educational events. They spoke with engineering and media students at Temple University in Philadelphia on February 27 to discuss life and research aboard the orbital outpost.

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