This paper describes a low cost hyper-spectral mission based around the CHRIS instrument that has been developed at Sira Technology Ltd. The CHRIS instrument is flying on the ESA PROBA platform, a small agile satellite of the 100kg class, which was launch in October 2001. The instrument typically acquires more than 300 hyper-spectral images each year via two European ground stations. Today this instrument provides the highest sampling capability of any space-borne hyper-spectral instrument. The main purpose of the instrument is to provide images of land areas, although the applications have extended to include coastal monitoring. The platform provides pointing in both across-track and along-track directions, for target acquisition and slow pitch during imaging (motion compensation). An observational mission has been developed around the facility and this is catering for some 40 or so Principal Investigators (PI) around the world, including Europe, North America, Australia and China with around 100 observational sites
