Living and Working in Space

Living in space is extraordinary — and very challenging. On board the International Space Station (ISS), astronauts experience microgravity: everything floats, including the astronauts themselves. Simple tasks on Earth, like drinking a glass of water or washing your hair, require completely different techniques in space.

A common misunderstanding is that there is no gravity in space. In fact, gravity is still strong at the height of the ISS. Astronauts float because the whole station, and everyone in it, is constantly falling around the Earth together — a state called free fall. Because everything falls at the same rate, nothing feels heavy. That is the real reason they appear weightless.

Astronauts drink water from sealed pouches with straws and eat specially prepared food — some dried and rehydrated with water, some in pouches or tins. Crumbs are a real problem in microgravity because they float around the cabin and can get into equipment, so food like bread is avoided. Instead, astronauts often use tortillas, which barely crumble at all.

Even going to the toilet is tricky without gravity to pull waste down. Space toilets use gentle suction, like a vacuum cleaner, to keep everything in place. Water is so precious on the ISS that the station recycles almost everything — including sweat and even urine — cleaning it back into safe drinking water. Astronauts joke that 'today's coffee is tomorrow's coffee'.

Outside the ISS astronauts perform spacewalks, also called EVAs (Extra-Vehicular Activities). They wear a pressurised spacesuit that provides oxygen to breathe, maintains comfortable pressure, shields them from radiation, and protects against extreme temperatures ranging from −120°C in shadow to +120°C in sunlight. A spacesuit is really a tiny personal spacecraft.

Spending months in space changes the human body in fascinating ways. Without gravity squashing them down, astronauts can grow a few centimetres taller while in orbit. Their hearts and bodily fluids shift around, often making their faces look puffy at first. When they return to Earth, it can take weeks to get used to gravity again.