External structure


The Discovery shuttle carried on board
the Station’s first exterior frame,
a truss structure in the form of a beam,
as well as another conical adapter
for docking to the Station.

On October 11, 2000, Shuttle Discovery flew to the International Space Station for an assembly mission that would last 12 days and 21 hours and during which it would circle the Earth 203 times and travel 8.5 million kilometers. Its crew members installed the Z-1 structure and the pressurized adapter, and they completed four spacewalks.

Z-1 is the first exterior frame element that will allow the first American solar panels to be temporarily attached to the Unity connection module for power supply. A Ku-band communication system was also installed to allow scientific activities to be carried out and the establishment of an American television network during flight 6A. In addition, CMG (for Control Moment Gyros) gyroscopes, weighing approximately 270 kilograms, were installed to provide non-propulsive attitude control when activated during flight 5A. The pressurized adapter was installed to allow docking of the shuttle for the installation of the solar panels during flight 4A and the laboratory during flight 5A.

Two teams of space walkers and an experienced robotic arm operator, over four trips, worked closely together to install the Z-1 structure on the US Unity docking module and to deliver the third pressurized adapter to it. ‘ISS in order to allow the docking of the elements of the Station and the mooring of the shuttles.

The Z-1 structure, somewhat resembling a beam, was the first permanent element of the structure of the Station and made it possible to prepare the arrival of the segments of the large beam of the ISS. The Z-1 structure will also serve as a platform on which the large American solar panels will be mounted during the shuttle’s next assembly flight, flight STS-97. The Z-1 structure contains four gyroscopes which will be used to correctly orient the ISS in orbit.

On October 24, 2000, Discovery landed on runway 22 at Edwards Air Force Base in California after a successful mission