Space Station Practice

STS-80 seemed to have it all: two satellite deployments and retrievals, a record-smashing 18-day mission, a range of life and microgravity science experiments and the oldest person yet to fly into space. But one thing it did not have - and which harked back to Bill Lenoir and Joe Allen's ill-fated experience in late 1982 - was a spacewalk, after a balky airlock handle prevented two STS-80 crew members from becoming the first astronauts to venture outside Columbia in orbit. Nonetheless, it was, as Commander Ken Cockrell put it before liftoff, ''a little warm-up for operating the space station''.

So it was that, in the early hours of 23 November 1996, less than four days into the mission, no fewer than three separate spacecraft trailed one another in a delicate orbital ballet. One was the venerable Columbia herself, while the others were an odd, disk-shaped contraption known as the Wake Shield Facility (WSF) and a German-built facility called the Shuttle Pallet Satellite (SPAS). The latter had flown numerous times since June 1983, and can be thanked for taking the first-ever photograph of a Shuttle in orbit when it photographed Challenger during STS-7.

Originally intended as a means of providing a standardised support structure and resources for research payloads, SPAS flew successfully on three occasions, carrying its first major scientific instrument - an experimental infrared background signature survey for the US Department of Defense - on board Discovery on STS-39 in April 1991. It was later superseded by a heavily upgraded version known as 'ASTROSPAS', which first flew in September 1993, transporting an astronomical spectro-meter-and-telescope package called the Orbiting and Retrievable Far and Extreme Ultraviolet Spectrometer (ORFEUS) into space.

Space station practice 279

Space station practice 279

The STS-80 crew depart the Operations and Checkout Building, bound for the launch pad. Left to right in pressure suits are Kent Rominger, Tammy Jernigan, Story Musgrave, Tom Jones and Ken Cockrell.

So successful was the maiden voyage of this package that, on STS-80, it flew again. Both ASTRO-SPAS and ORFEUS were the product of a cooperative venture between NASA and the German space agency, DARA. As well as offering support and data-handling services to its scientific package, the satellite provided energy from its powerful lithium-sulphur dioxide battery and achieved ultra-stable attitude control with a three-axis-stabilised cold-gas system, in combination with an onboard star tracker and specially developed GPS receiver. It was planned that, on STS-80, ORFEUS-SPAS-2 would spend up to 14 days in quasi-autonomous flight alongside Columbia.

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