What do you think of this fact?
For most people, seeing a sunrise means setting an alarm and suffering. On the International Space Station, you basically get them on subscription.
Around the world in 90 minutes
According to EarthSky, the ISS flies about 400 kilometers up at roughly 27,500 kilometers per hour. NASA says it takes about 90 minutes to go around Earth once, which adds up to 16 orbits in 24 hours.
On every orbit, the station passes over the day side and the night side of the planet. The result: 16 sunrises and 16 sunsets per day. In a single day, the crew sees more sunrises than you get in two weeks.
On the side, according to NASA, the station covers roughly the distance to the Moon and back in about a day.
Sleeping while the Sun parties
As beautiful as that sounds, it is a problem for the body. Our internal rhythm follows the switch between light and dark, and on the ISS that switch comes every few dozen minutes. According to the Canadian Space Agency, this makes a regular sleep pattern hard to keep.
The solution is a fixed schedule instead of sunlight. According to the agency, crew members are allotted about 8.5 hours of sleep a day, but many feel fully rested after about 6 hours. A sleep mask blocks the constant light, and earplugs block the station’s noise. Anyone not sleeping in a sleep compartment simply attaches their sleeping bag to the floor, ceiling or wall.
Bonus fact: The station runs on Greenwich Mean Time, which the Canadian Space Agency describes as a compromise between mission control centers in Houston and Moscow.
Up there, being an early bird is a seriously exhausting job.