Mars Global Surveyor Aerobraking At Mars

On September 12, 1997, the Mars Global Surveyor (MGS) spacecraft was successfully inserted into a highly elliptical capture orbit about Mars. To establish the required mapping orbit, the MGS spacecraft must supplement its propulsive capabilities by aerobraking. This paper describes the aerobraking strategy developed for the MGS mission. This description includes the aerobraking constraints imposed on the trajectory design, the approach toward aerobraking trajectory control, and the aerobraking flight profile that resulted from the planning activities that occurred after launch. The initial aerobraking results are contrasted to the planned baseline trajectory.Additionally, this paper describes the aerobraking progress of the MGS spacecraft made following a three week aerobraking hiatus that occurred in October 1997. This hiatus was initiated in order to provide time to evaluate the viability of continuing aerobraking with newly discovered damage to one of the two spacecraft's solar arrays. The results of the stand-down forced a major re evaluation of the MGS mission and this paper briefly describes the new mission outlook.