There has been an international crew aboard the International Space Station (ISS) since 2000. Why? What is it about the idea of a space station that has made it so important for the nations of the world. It seems that there is a fundamental belief about its importance that is very nearly universal. And it has a long history.
From virtually the beginning of the twentieth century, those interested in the human exploration of space have viewed as central to that endeavor the building of a massive Earth-orbital space station that would serve as the jumping off point to the Moon and the planets. Always, space exploration enthusiasts believed, a permanently-occupied space station was a necessary outpost in the new frontier of space. The more technically-minded recognized that once humans had achieved Earth-orbit about 200 miles up, the presumed location of any space station, the vast majority of the atmosphere and the gravity well had been conquered and that persons were now about halfway to anywhere they might want to go.
As early as 1869 Edward Everett Hale, a New England writer and social critic, published a short story in the Atlantic Monthly entitled “The Brick Moon.” The first known proposal for an orbital satellite around the Earth, Hale described how a satellite in polar orbit could be used as a navigational aid to ocean-going vessels. When the heroes of the story substitute a brick moon for this ring—brick because it could withstand fire—it is hurled into orbit 5,000 miles above the Earth. An accident sends the brick moon off prematurely, however, while 37 construction workers and other people were aboard it. In contrast to what is now known about the vacuum of space, these people lived on the outer part of the brick moon, raised food, and enjoyed an almost utopian existence.
Russian schoolteacher Konstantin E. Tsiolkovskiy also studied the possibility of establishing a space station in Earth-orbit before the beginning of the twentieth century. Tsiolkovskiy even discussed the feasibility of building a dramatic wheeled space station that rotated slowly to approximate gravity with centrifugal force. During the 1920s Romanian-German space flight theorist Hermann Oberth and Austrian engineer Hermann Noordung both elaborated on the concept of the orbital space station as a base for voyages into space. In Nordung’s case, the technical attributes of a space station to support planetary exploration took up the bulk of his 1929 book, Das Problem der Befahrung des Weltraums (The Problem of Space Travel).
In part because of this persistent vision of human destiny to explore the Solar System and the central role of a space station in facilitating this goal, studies of space station configurations had been an important part of NASA planning in the 1960s. NASA scientists and engineers pressed for these studies because a space station met the needs of the agency for an orbital laboratory, observatory, industrial plant, launching platform, and drydock. The station, however, was forced first to the bottom of the priority heap in 1961 with the Kennedy decision to land an American on the Moon by the end of the decade. With that mandate, there was no time to develop a space station in spite of the fact that virtually everyone in NASA recognized its use for exploration beyond Earth orbit. It surfaced as the foremost NASA program even while Apollo became a reality in the latter 1960s, but took several unusual turns before emerging as the principal project of the agency at the end of the twentieth century.
Both the United States and the Soviet Union pursued space stations in the 1970s. The Soviet Almaz and Salyut series of space stations operated until the building of Mir in the 1980s. NASA flew the Skylab orbital workshop in 1973-1974. Then in 1984, NASA began working on another space station; it eventually morphed into the ISS. Fundamentally, we have always believed the space station is necessary to facilitate other activities in space, especially human missions to Mars.