One down one to go

Africa. It had been attached to the ASE by means of five attachment points, which were released when locking pins were retracted. An explosive device then released a spring which pushed Leasat over the payload bay sill like a frisbee at a velocity of about 4.6 cm/s, spinning at a couple of revolutions per minute for stability.

''Houston, we had a good deploy,'' Low radioed from his station on Columbia's aft flight deck.

''David, we copy and congratulations,'' responded Capcom Tammy Jernigan.

A few minutes after the satellite had left Columbia's vicinity, Brandenstein and Wetherbee performed a separation manoeuvre to create a safe distance before Leasat's first engine burn. The satellite's Hughes manufacturers were pleased: ''It was as good as you can get. Everything looks great,'' said spokesman Tom Bracken later that day. A series of manoeuvres by the satellite's own propulsion system were required to achieve its geosynchronous orbital slot. The first, at 1:53:48 pm, involved Leasat firing its solid-fuel motor to boost itself firstly into an elliptical transfer orbit with an apogee of 13,200 km, which was later circularised and raised to geosynchronous altitude.

During this time, Dunbar again uncradled the RMS and used one of its cameras to photograph the first Leasat burn. Several additional manoeuvres were made by the satellite to achieve geosynchronous orbit, but it had settled into its correct 'slot' over the Pacific Ocean at 177 degrees West longitude by 13 January. After a month-long period of checks, it was declared operational and joined the other three Leasats. Later in 1990 and early 1991, it was employed to support military communications during Operations Desert Shield and Desert Storm in Iraq.

The satellite finally retired from US government service in February 1998, bringing to an end more than a decade of Leasat operations. However, its usefulness was not yet over. Under a multi-million-dollar contract with the Australian Defence Force, in May of that year it was moved into a new orbital slot at 156 degrees East longitude for use by the Royal Australian Navy. It was a reprieve for the satellite: according to Hughes' spokesman Ronald Swanson, ''[it] was literally within days of being propelled into [a] useless ['graveyard'] orbit, since its service to the Department of Defense had been completed''.

After the successful deployment of Leasat, Columbia's crew turned their attention to the retrieval of the LDEF. At the time of their launch, they were trailing the satellite by about 2,730 km, closing in at some 60 km per orbit. Three flawless manoeuvres were performed by Brandenstein and Wetherbee on 9 and 10 January to help to close the gap between the crew and the LDEF, and an excited Flight Director Bill Reeves exulted, ''Everything is 'go' for the rendezvous. The crew and the ground feel very excited and are looking forward to it.''

On the morning of 12 January, the astronauts were awakened by music from Mission Control: 'Bring It Home', to the tune of 'Let It Snow'. Due to the sensitivity of the LDEF's experiments, their approach was as unobtrusive as possible to minimise contamination. From a distance of 40 km down to 1.6 km, Columbia's radar and star-tracker locked onto their target and guided Brandenstein closer. He then took manual control, passing 'below' and 'ahead' of the satellite, then pitching the Shuttle's nose 'upwards' to achieve a position directly 'above' the LDEF.

Leasat-5 drifts away from Columbia on 10 January 1990.

''You don't want to close too fast with something that big and massive,'' Wetherbee would say later. ''With the risks involved, you want to keep the closure very controlled and Dan was able to do that.''

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