The Space Shuttle Atlantis was launched on 5 May 1989 and, soon after, its pay-load, the Magellan Venus Radar Mapper, was successfully boosted toward Venus by an Inertial Upper Stage. Shuttle flights carrying payloads require a thermal integration analysis to predict and evaluate the integrated vehicle's thermal radiation exchange factors, environmental heat loads, and temperatures as a function of mission time. This was accomplished by using geometric and thermal mathematical models for hot and cold case mission timelines. This paper outlines the mission timeline and discusses these models, environments, and assumptions. Components that exceed their design temperature limits in the nominal missions are identified and discussed.