SPACE STATIONS

In a space station, a large crewed spacecraft orbiting Earth, astronauts can live and work in space for long periods. The INTERNATIONAL SPACE STATION (ISS) is the biggest structure ever to be built in space.

WHAT ARE SPACE STATIONS USED FOR?

Astronauts carry out research in space stations. They examine the behavior of materials and living things in a microgravity (near-weightless) environment. They also study the effect of space flight on the human body.

HOW ARE SPACE STATIONS BUILT?

Early space stations such as Russia’s Salyuts and the US Skylab were built on Earth and launched into orbit as complete units. Larger stations such as Mir and the ISS are assembled in orbit from modules (sections) that are ferried up from Earth one at a time.

MIR

Mir was permanently crewed by two or three cosmonauts, plus guests from dozens of nations. Mir fell back to Earth in 2001.

THE ISS

When completed, the International Space Station will be the biggest, most complex space station ever. With a length of 260 ft (80 m) and a wingspan of 360 ft (110 m), it will have a mass of nearly 550 tons (500 metric tons).

INTERNATIONAL SPACE STATION

Currently being built from more than 100 separate main parts, the ISS will be a global research center in space. The United States, through the National Aeronautics and Space Administration (NASA), provides most of the station hardware and is in charge of construction. Russia, Europe (through the European Space Agency), Japan, and Canada also supply major units.

WHAT IS IT LIKE INSIDE THE ISS?

The living and work space on the ISS is the same size as the passenger space on two 747 aircraft. There are four laboratory modules where astronauts carry out scientific research. The main living accommodation, for a crew of seven, is in the US habitation module. It has two decks and contains sleep stations, galley (kitchen), medical facility, gym, toilet, and shower in a space about 26 ft (8 m) long and 13 ft (4 m) wide.

EVA ON THE ISS

Robots on the shuttle and the ISS connect new sections of the station, but spacewalking astronauts are needed to complete the job. More than 850 hours of extravehicular activity (EVA) will be required before assembly of the station is complete. Afterward, astronauts will have to make regular EVAs to carry out maintenance and repairs.

Copyright © 2007 Dorling Kindersley