For at least a century, people have imagined a home in space. Both the United States and the Soviet Union saw space stations as a further use of the technical capabilities developed in the Space Race. A base in Earth orbit can serve many purposes:

• Biomedical research laboratory
• Microgravity research laboratory and materials processing facility
• Platform for astronomical and Earth-observing scientific instruments
• Training ground for long-duration spaceflight in preparation for human missions elsewhere in the solar system
• Way-station to the Moon or Mars
• Focus for advancing technology and maintaining spaceflight capabilities

SPACE STATIONS FOR THE SOVIET UNION AND RUSSIA

In the 1960s during the race to the Moon, the Soviets began to build hardware that in the 1970s became the world's first space station, Salyut. Since then the Soviets--and then the Russians--methodically improved the habitability and reliability of space systems through a succession of space stations. They have maintained an almost continuous presence in Earth orbit.

SPACE STATION PLANS FOR THE UNITED STATES

Under Presidents Ronald Reagan and George Bush, concepts for space station Freedom evolved through several redesigns, but none received both White House and Congressional approval. At President Bill Clinton's direction in 1993, the concept was scaled back, made less costly, and transformed into the International Space Station.