centaurg

Actually, this is the short G version which was intended for GSO missions. The the G' (G Prime) was the long version intended for the really heavy payloads going to GSO or interplanetary trajectories. There was several Gs in production at the time of the program's cancellation in 1986. Some had been bought by the DoD and one had been bought by NASA for the Venus Radar Mapping mission (later renamed to Magellan which launched on a IUS in May 1989).

These are models of the two variants of Shuttle Centaur. On the right is Centaur G-prime, to be used for civilian (NASA) interplanetary probes launched from KSC, Florida. On the left is Centaur G, to be used for military (USAF) polar spy satellites to be launched from Vandenberg AFB, California, and GEO satellites to be launched from KSC. The Challenger disaster ended the Shuttle Centaur program: Centaur G-prime flight articles were built but never flew, and the launch complex at Vandenberg AFB was built but never used. N.B.: The Centaur G-prime model (right) is shown with its payload, an interplanetary probe (probably Galileo), whereas the Centaur G model (left) does not include a model of its payload, which would have been classified information.

Here's a link to a great article about Shuttle-Centaur: www.cleveland.com/science/index.ssf/2011/12/long-forgotte...

Excellent detail, thanks! "CISS" stands for Centaur Integrated Support Structure, and this "Proof Load Test" took place on 6-24-86. The CISS was specific for Shuttle Centaur (Centaur G/G'), which was being developed for use until the Challenger disaster on January 28, 1986. The Shuttle Centaur program was officially ended 5 months later. So it's very interesting that this work is taking place in June of 1986, after the program was cancelled.