This is a lesson about the role of computers in space exploration. Learners will investigate various ways to improve mission design to maximize the scientific return. In the first activity, the students examine how the use of flowcharts can help make computer programs error-free and efficient, in this way making the spacecraft more reliable. In the second activity, the students investigate how data can be compressed for transmission over limited bandwidth. By the end of the lesson, the students come to realize that the wealth of data gathered by spacecraft is useless if it cannot be transmitted safely and efficiently to the scientists on the Earth.