As Russian cosmonauts and engineers prepare to return next week to their nation's presumed-dead space station, it is interesting to look back on the bumpy, and sometimes tragic road that led to Mir and Russia's position as the leading authority in space station technology and achievements.

Although many worldwide space agencies, including Russia's, are devoting their energies these days to building the International Space Station, it was the Soviet Union that orbited the first space station in 1971. It took nearly two years for the United States to match with its Skylab what the U.S.S.R. had achieved with Salyut 1.

In 1969, the Soviet space program reached a critical crossroads. While U.S. astronauts walked on the moon, the Soviet Union's own effort to launch a giant moon rocket resulted in two disastrous explosions that put the program years behind schedule.

In this climate, at Sergei Korolev's TsKBEM design bureau (now RKK Energia) -- which in the 1950s and 1960s pioneered space exploration -- many engineers were looking for a new direction. At the time, their competitors within the Soviet space industry, led by charismatic leader and talented engineer Vladimir Chelomei, were busy developing a space station primarily for military purposes.

In an ambitious, super-secret project called Almaz, Chelomei envisioned a piloted orbiting outpost equipped with powerful spy cameras, radars and even self-defense guns. It would also include heavy supply ships and multiple reentry capsules.

The complex program, however, fell victim to the antagonistic politics within the Soviet defense industry. Chelomei, who rose to prominence during Khrushchev's reign, fell out of favor with the new government at the end of the 1960s. After that, Almaz was plagued with delays.

The engineers at Korolev's design bureau proposed that the government borrow Chelomei's existing hardware to build a bare-bones space station. This, they said, could be launched within a year after approval and well before NASA's own Skylab outpost, which was expected to materialize in mid-1972.

Such marathon deadlines, the engineers said, would be possible by outfitting Chelomei's space station body with the "guts" from the flight-proven Soyuz spacecraft, including a critical propulsion unit and solar arrays.

By the end of 1969, Dimitry Ustinov, a powerful member of the Communist Party's Central Committee overseeing the space program -- known in the industry as Uncle Mitya, and also as Chelomei's stolid personal adversary -- signed onto the project.

On February 9, 1970, the Soviet government officially endorsed the program, under secret code DOS 7-K. As promised, at the beginning of 1971, DOS 1, the world's first space station was ready for launch.

On April 19, 1971, a Proton rocket successfully lifted DOS 1 into orbit. Shortly before launch, the name "Zarya" ("sunrise") was painted on the side of the station as its official name, however, officials in Moscow ordered the developers to change the name, apparently because a Chinese spacecraft had already been given that name. Nobody tried to paint the new name on the station. Nonetheless, the official Soviet press called the station as Salyut 1, which can be translated as "salute" or "fireworks."

The first space station crew included Vladimir Shatalov, Alexei Eliseev and Nikolai Rukavishnikov. They took off from Baikonur, in the then Soviet republic of Kazakhstan, in Soyuz 10 on April 23, 1971. In orbit, their spacecraft docked with Salyut, but the docking mechanism on Soyuz was damaged in the process, preventing the crew from ever entering the station.

Fortunately, the docking port on Salyut 1 remained intact. The next crew, Georgy Dobrovoslkiy, Vladimir Volkov and Victor Patsaev, was launched on June 6, 1971. This time, the docking was successful and they entered the station.

The crew spent 23 productive days in orbit, breaking spaceflight duration records and bringing invaluable experience in the program. Then on June 30, at the very end of the mission, disaster struck as the Soyuz 11 spacecraft reentered the atmosphere.

A faulty pressure valve in the reentry capsule opened before they had entered the atmosphere. The air inside the return capsule escaped into space within seconds, creating a vacuum. The cosmonauts, who wore no pressure suits, died from decompression, apparently before they could even realize what was going on.

Soviet spacecraft designers, shocked by the catastrophe, initiated major and lengthy redesigns on the Soyuz spacecraft to increase safety. Never again would Soviet or Russian cosmonauts go into orbit without pressure suits. To make room for the emergency life-support system needed for the pressure suits, the standard Soyuz crew was reduced from three to two.

Though Salyut 1 had to be discarded on October 11, 1971, for the next 15 years the Soviets produced several successor stations up to Salyut 7. That pioneering experience paved the way for the 1986 launch of Mir -- a station with six docking ports -- that would eventually grow into the multi-module space complex currently in orbit.

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