The HYDRA from Sodern is a Star Tracker with Mass 1400 g (OH), 1800 g (EU), Slew Rate 5 to 8 Degree/sec, Data Update Rate 8 Hz, 10 Hz, 12 Hz, 16 Hz, 20 Hz, 30 Hz, Supply Voltage 21 to 52 V, Power Consumption 0.8 to 1 W (OH), 6 to 7 W (EU). More details for HYDRA can be seen below.