You may have seen it moving swiftly across the night sky, or tracked it using NASA's Spot The Station, and wondered: What is life like on the International Space Station? And who is living on the International Space Station? The ISS is a joint project between the European Space Agency and four partner nations: the United States, Russia, Japan, and Canada.
It makes its home in low Earth orbit approximately 250 miles above the Earth's surface, traveling at just under 5 miles per second - that's approximately 17,000 miles per hour. It is the most expensive single item ever built, costing an estimated $150 billion.
Those lucky enough to board this otherworldly vessel experience spectacular sunrises and sunsets approximately every 45 minutes, and the research on the ISS is conducted in a one-of-a-kind laboratory - outer space. It may even hold the key to humankind's next great space ambition: a mission to Mars with humans aboard. While waiting for that to happen, NASA and astronauts are not shy about answering the question: "What is it like to live on the International Space Station?"
Even though water is the most abundant resource on Earth, the supply on the ISS is limited. Two water filtering systems are available: one for the Americans, and one for the Russians. The American astronauts filter their own urine as well as that of their Russian counterparts, although the latter refuse to drink it. All astronauts visiting the ISS, however, drink recycled wash water. The station holds about 2,000 liters of water in reserve.
Layne Carter, water subsystem manager for the ISS, told Bloomberg the recycled urine "tastes like bottled water," and suggested the water setup isn't as disgusting as people might think:
Before you cringe at the thought of drinking your leftover wash water and your leftover urine, keep in mind that the water that we end up with is purer than most of the water that you drink at home. That makes the International Space Station its own self-contained environment.
Since 1998, astronauts have completed 224 spacewalks at the ISS. Most spacewalks help maintain the exterior of the ISS. Preparation is key to safety, and lasts nearly a full day. It begins with decompression, which is the same procedure deep divers use when returning from the depths of the ocean. For maximum mobility and protection from the absence of pressure in space, an astronaut's spacesuit is pressurized during the spacewalk to about one-third of the pressure experienced by those inside the ISS.
During a spacewalk, astronauts have to breathe pure oxygen, because the amount of oxygen in regular air is insufficient at such low pressure. One hour before the spacewalk, they begin to breathe pure oxygen through a mask, which prepares them for breathing it during the spacewalk.
The decompressed airlock is connected to another compartment that is unpressurized and leads to outside the ISS. The astronaut puts on the full spacesuit inside the airlock, then the airlock is sealed. The pressure inside is gradually decreased. Once the appropriate pressure is reached, the spacewalker pulls themselves through the outer hatch, and the spacewalk begins. The length of a spacewalk varies according to its mission, but generally lasts about six hours, and the astronaut is fully tethered for safety at all times.
Space inside the ISS is limited, and with a few other astronaut roommates, living quarters are small, but efficiently designed. Inside a room the size of a phone booth is a sleeping bag affixed to the wall that keeps astronauts from floating around while asleep.
Two computers are in the sleeping quarters, one for official business, and the other for personal business that includes internet access. This setup allows the crew to communicate with family and friends, using a camera and headphones for video calling. A personal space that is not much bigger than a human can be challenging, but cozy at the same time.
Using the toilet in space can be tricky. NASA shared the following details about space hygiene:
The astronauts have to position themselves on the toilet seat, using leg restraints and thigh bars. The toilet basically works like a vacuum cleaner, with fans that suck air and waste into the commode. Each astronaut has a personal urinal funnel, which has to be attached to the hose's adapter. Fans suck air and urine through the funnel and hose into the wastewater tank.