An Urgent Mission

When Space Shuttle Challenger reached orbit at the beginning of April 1984, the main objective of her week-long STS-41C mission had been the retrieval, repair and redeployment of NASA's Solar Max satellite. This was accomplished in a pair of spectacular spacewalks and deft handling of the Canadian-built RMS mechanical arm.

However, in order for the Solar Max retrieval to go ahead - and to make room for it in Challenger's payload bay - another satellite had first to be deployed. That satellite was a 12-sided, bus-sized structure called the Long Duration Exposure Facility (LDEF), which, as its name implies, was intended to accommodate experiments that required exposure to the hostile environment of low-Earth orbit for a protracted length of time. No one could possibly have known, at the time of the LDEF's launch, exactly how long the huge satellite would remain in space before being retrieved by another Shuttle and returned to Earth. NASA originally intended to retrieve the LDEF during Brewster Shaw's STS-51D mission in February 1985, but that was delayed. By the time Challenger exploded, the retrieval had been scheduled for STS-61I in the autumn of 1986.

Almost three years after the loss of Challenger, the LDEF was in a precarious state as it entered its sixth year of operations. Trajectory planners predicted that by March 1990, at the latest, it would be unable to maintain itself in orbit and would tumble back to Earth, burning up in the atmosphere. As many of the experiments on board the LDEF were expected to provide invaluable data as NASA developed new materials to build its Earth-orbital space station - at the time known as 'Freedom' -it was imperative that a Shuttle bring it home.

That was the job of Dan Brandenstein's STS-32 crew on Columbia's second postChallenger mission. As chief of the Astronaut Office - a position he had taken over from John Young in mid-1987 - he had already flown two Shuttle missions, including the first nighttime liftoff and landing on STS-8. Privately, some astronauts have speculated that Brandenstein's position enabled him to pick for himself the two best missions of the early 1990s: the LDEF retrieval and the ambitious first flight of the new Space Shuttle Endeavour, which had been built to replace Challenger.

Joining Brandenstein for STS-32 were Pilot Jim Wetherbee and Mission Specialists Bonnie Dunbar, Marsha Ivins and David Low; of these, Dunbar was on her second spaceflight and the other three were first-timers. Interestingly, Dunbar was the only member of the original LDEF-retrieval crew from STS-61I to fly on STS-32. It was Dunbar's job to operate the RMS: plucking the satellite out of space and planting it safely into Columbia's payload bay. Brandenstein and Wetherbee would conduct the delicate orbital ballet to reach the LDEF and Ivins would photodocument the entire procedure.

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