The Galileo mission to Jupiter and Doppler wind measurements

The results of previous atmospheric entry missions are reviewed, including the Pioneer Venus, Venera, and Vega missions. The Galileo mission is then described. The dual-vehicle (probe and orbiter) spacecraft was launched in October 1989 and will reach Jupiter in December 1995. The spacecraft and its hardware are described. The method used to measure the variation of wind velocities with altitude in the upper Jovian atmosphere, a key objective of the mission, is examined. The radio propagation environment of that atmosphere and its effects on the probe signal are discussed. Other errors that can affect the frequency of the received telemetry and thereby reduce the accuracy of the recovered wind profile are considered.<>