TopSat: Lessons learned from a small satellite mission

The UK's "TopSat" programme has been used to demonstrate the ability to build and operate a low-cost optical satellite capable of generating timely high quality imagery for a wide range of applications. Rapid end-to-end timeliness has been combined with a low-cost approach, leading to a world leading performance to-cost ratio. Historically, end-to-end timeliness has been a major constraint for space-based systems. During demonstrations using the TopSat spacecraft and RAPIDS mobile ground station, a total end-to-end timeliness (i.e. from image selection to image delivery) of less than 37 minutes was achieved. TopSat and missions of this class are set to revolutionise the space remote sensing business, through reductions in costs and thus greater numbers of spacecraft. This will allow missions to be tailored much more exclusively to the requirements of major users.