The German Aerospace Center (DLR) Bi-spectral Infrared Detection (BIRD) small satellite is a technology demonstrator of new infrared push-broom sensors dedicated to recognition and quantitative characterisation of thermal processes on the Earth surface. BIRD was successfully piggy-back launched on October 22, 2001 with an Indian Polar Satellite Launch Vehicle (PSLV-C3) into a circular sun-synchronous orbit with an altitude of 572 km and a North - South local equator crossing time at 10:30 h. Besides cameras working in the visible and near infrared spectral range there are two cameras working in the middle infrared (MIR, 3.4 – 4.2 µm) and in the thermal spectral range (TIR, 8.5 – 9.3 µm) respectively. The objective is to validate these two cameras in cooperation with the Koldewey-Station in Ny-Ålesund. Therefore meteorological and aerological data as well as radiation measuring data will be used.