Radiator element for the US Space Station, on test during Shuttle Mission STS-29. The radiator element is the long object running along the side of the Shuttle's cargo bay. The unit is called the Space Station Heat Pipe Advanced Radiator Element (SHARE), and is part of a programme designed to test components for the Freedom space station. The test was not able to be carried out, as bubbles in the ammonia coolant prevented its circulation. Mission STS-29 was launched on Shuttle Discovery on 13 March 1989, successfully completing the primary task of deploying the TDRS-D communications satellite six hours into the flight. The mission ended safely on 18 March 1989.