The STD 15 from Sodern is a Dual Conical Scanning Earth Sensor that has an accuracy of 0.035 deg (Degree Bias Error). It has an output data rate of 1.25 Hz and noise of 0.015 deg. This sensor has been operated on several telecommunication satellites such as the HOT BIRD 2, TC2-B, and HELASAT. It has a mass of 3.4 Kg. This sensor requires a supply voltage of 20-55V and has a power consumption of up to 6.5 W. It. It has an infrared bolometer to detect earth-to-space and space-to-earth transitions and dual-track scanning patterns to increase accuracy. This sensor measures 168 x 206 x 206 mm and is ideal for measuring pitch and roll on board GEO satellites since it can meet stringent requirements and environmental constraints of GEO missions.