Life Aboard the International Space Station

Imagine a home where your toothbrush floats away if you let go of it,

your sleeping bag hangs on the wall and the sun rises every hour and a half.

For the astronauts who have lived aboard the International Space Station, that is simply everyday life.

Here is what it is really like to live and work in orbit: how the station is laid out,

what a typical day looks like, how crews sleep, wash and stay fit,

and what they do when the work is done.

A Home the Length of a Football Field

The International Space Station is a joint project of the space agencies of the United States, Russia, Europe, Japan and Canada.

Assembly began in 1998, when the first module was launched, and its first resident crew arrived in November 2000.

Over the following years, dozens of launches added laboratories, living quarters, solar arrays and docking ports.

The finished structure stretches about 109 meters (357 feet) from end to end, roughly the length of an American football field.

Inside, its connected modules offer more living space than a six-bedroom house.

The station orbits about 400 kilometers (250 miles) above Earth at roughly 28,000 kilometers per hour (17,500 miles per hour),

circling the planet about every 90 minutes. That means crews see around 16 sunrises and 16 sunsets every day.

A Day on the Station

With the sun rising and setting constantly, the station needs an artificial clock.

Crews follow Coordinated Universal Time, the same reference used for world timekeeping,

and mission control teams on the ground plan every day in detail, often down to five-minute blocks.

A typical weekday looks something like this:

1. Wake up, wash and eat breakfast.
2. Join a morning planning conference with flight controllers in several countries.
3. Work through the morning on experiments, maintenance and repairs.
4. Stop for lunch, often shared with crewmates from other countries.
5. Complete an exercise session, usually lasting around two hours.
6. Finish the afternoon's tasks and join an evening check-in with the ground.
7. Enjoy some free time, then sleep, with roughly eight hours set aside.

Weekends are lighter, with time for housekeeping, calls to family and a little rest.

Sleeping in Weightlessness

Each astronaut has a tiny private crew quarter about the size of a phone booth,

with a sleeping bag fastened to the wall, a light, a laptop and a few personal items such as photographs.

Without gravity, there is no up or down, so sleeping upright feels no different from lying flat.

Airflow matters more than you might think. On Earth, the warm air you exhale rises away from your face.

In weightlessness, air does not circulate on its own, so exhaled carbon dioxide can collect around your head.

Fans keep the air moving in every sleeping area, and many astronauts wear earplugs because the station hums constantly with pumps and ventilation.

Eye masks help too, since the next sunrise is never more than about 45 minutes away.

Staying Clean Without a Shower

Water does not flow in orbit; it clings to skin and drifts in wobbling blobs.

Ordinary showers and sinks would be useless, so personal hygiene works differently:

• Washing: Astronauts use damp towels, wet wipes and liquid soap that does not need rinsing.
• Hair: A no-rinse shampoo is massaged in and toweled off, and short haircuts are done with clippers attached to a vacuum hose that catches the clippings.
• Teeth: Toothpaste is either swallowed or spat into a towel.
• The toilet: Instead of gravity, fans and suction pull waste away from the body.
• Laundry: There is no washing machine. Clothes are worn for days at a time, then packed away as trash.

The station also recovers water from humidity in the air, from sweat and even from urine, purifying it until it is clean enough to drink.

Recycling the large majority of its water saves huge amounts of weight that would otherwise have to be launched from Earth.

Exercise Is Not Optional

In weightlessness, muscles and bones that normally fight gravity start to weaken.

To slow that loss, astronauts exercise for about two hours almost every day.

They run on a treadmill while elastic straps and a harness hold them against the belt,

pedal a stationary bike that has no seat,

and lift weights on a resistance machine that uses vacuum cylinders to create load.

The workouts also help the heart and blood vessels stay in shape for the return to gravity.

Crews often say the exercise sessions are among the most important parts of their day.

Work, Science and Upkeep

The station is first and foremost a laboratory.

Over the years, crews have carried out many thousands of hours of research in biology, medicine, physics, materials science and Earth observation.

Some experiments study how flames, fluids and crystals behave without gravity.

Others use the astronauts themselves as test subjects, tracking changes to their eyes, bones, hearts and immune systems.

A good share of the week also goes to keeping the station running.

Astronauts replace filters, repair pumps, track down leaks and swap out equipment, much like caretakers of a very complicated building.

They also practice emergency drills for fires, air leaks and toxic spills, and use a large robotic arm to help capture arriving cargo ships.

Everything must be secured. Tools are stored with hook-and-loop fasteners, bungee cords and clips,

and small items that escape tend to drift until they end up stuck to the screens of air intake vents,

which is often where missing objects are finally found.

Downtime and the View

In their free time, many astronauts head for the Cupola, a dome with seven windows that looks straight down at Earth.

From there they photograph hurricanes, auroras, city lights and deserts, and many describe the view as the highlight of their mission.

Crews also read, watch movies, play music and keep in touch with family through email, phone calls and video links.

Some talk with students on the ground using amateur radio.

Cargo ships occasionally bring care packages and a treat many crew members crave most: fresh fruit.

Frequently Asked Questions

Can you see the space station from the ground?

Yes.

It is one of the brightest objects in the night sky, looking like a steady, fast-moving white star with no blinking lights.

It is best seen shortly after sunset or before sunrise, when the station is lit by sunlight while your sky is dark.

Space agencies and astronomy apps publish pass predictions for your location.

How long do astronauts usually stay?

Most station expeditions have lasted around six months.

A few people have stayed close to a year, including NASA astronaut Scott Kelly and Russian cosmonaut Mikhail Kornienko,

who spent about 340 days aboard in 2015 and 2016.

What happens if someone gets sick or hurt?

Every crew includes members trained to handle basic medical care,

supported by a medical kit and by doctors on the ground who can advise over video.

For a serious emergency, spacecraft docked at the station can serve as lifeboats and bring the crew home within hours.

Life in Orbit, in Short

Life aboard the International Space Station is a mix of the extraordinary and the mundane: repairing a pump in the morning,

running an experiment no lab on Earth could host in the afternoon,

and watching the sun set over an ocean from a window in the evening.

The next time you see that bright point of light glide across the sky,

you will know a little more about the people living inside it.