International Space Station I 20th Anniversary
THE INTERNATIONAL SPACE STATION A Renaissance in Space Exploration and Research
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bout a century before humans had the technology to do anything about it, their longing to slip the bonds of Earth was overpowering enough to inspire some eerily prescient fantasies about living in space. “The Brick Moon,” perhaps the first written mention of a crewed space station, was a novella published serially in The Atlantic by Edward Everett Hale in 1869, four years after Jules Verne’s novel From the Earth to the Moon. Hale’s plot follows the narrator’s scholarly companions as they fashion a 200-foot sphere made of bricks – iron, the narrator explains, would have been too heavy – and accidentally launch it into space with 37 of them aboard. Though the brick moon’s inhabitants never figure out how to return to Earth, they survive by growing crops. By the 1960s, science (not to mention science fiction) had advanced considerably, to the point where the United States and the Soviet Union were launching manned spacecraft into orbit and were already
plotting how to apply their new technologies to support long-duration human spaceflight. With its Salyut program, the Soviet Union launched the first crewed space stations beginning in 1971. NASA research centers had been mulling rudimentary designs for an American space station since the early 1960s, based on a modified Apollo Command/ Service Module (CSM) with an attached laboratory. The Apollo Applications Program, formally launched in 1967, was focused on long-duration flights in low-Earth orbit, and led to the design of the American space station known as Skylab, which orbited Earth from 1973 to 1979. Today’s International Space Station bears imprints of both the Salyut and Skylab programs: A Soyuz capsule remained permanently docked at Salyut stations, to provide a means of emergency escape, while the Apollo CSM served the same function for Skylab. American and Soviet crews conducted experiments inside the modules and performed
A labeled artist’s conception of Apollo Applications Program (AAP) Skylab Cluster.
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spacewalks for exterior maintenance. The “second-generation” Salyut stations, Salyut 6 and 7, each had two ports to allow resupply by cargo spacecraft. The voluminous Skylab, built from a hollowed-out upper stage of NASA’s Saturn V moon rocket, was launched unmanned in May 1973 and visited by three-man astronaut crews who served on missions lasting between 28 and 84 days. The interior of Skylab, divided into tiered decks, was designed with habitability in mind, with a wardroom and private sleeping quarters separate from the laboratory. In 1969, as the Apollo Moon landing drew near, President Richard Nixon directed the formation of a Space Task Group that would define goals for NASA’s post-Apollo space program. The agency was on the threshold of history, about to do something unthinkable just years earlier, and the president wanted NASA to define how it might build on its ability to visit the Moon. The group envisioned a number of possibilities, including crewed satellites in Earth or lunar orbit, human travel to Mars, and “space transportation systems that carry their payloads into orbit and then return and land as a conventional jet aircraft.” In their report, the Space Task Group called for a space station to support the goal of landing on Mars. A budget that would fund both a space station and a reusable Space Transportation System (STS, or Space Shuttle, as it was soon colloquially known) seemed unlikely, so NASA focused first on the shuttle, as the use of expendable rockets to build and supply an orbiting base would exceed the cost of the base itself. A Space Shuttle, with a laboratory within it, would allow capabilities to be studied and harnessed while new technologies were researched. The Space Shuttle Program was already well underway by the time Skylab was launched into orbit.
NASA IMage
BY CRAIG COLLINS
