Abstract: A hybrid magnetometer and attitude determination and control system (hybrid magnetometer attitude determination and control system). Many scientific and commercial satellites in low-Earth orbit (LEO) use attitude determination and control systems that enable control and knowledge of the spacecraft's attitude (the orientation the spacecraft). The hybrid magnetometer and attitude determination and control system is a single package that can be integrated into small satellites, such as CubeSats, and consists of a three-axis search coil AC magnetometer and three-axis quad-mag DC magnetometer. The search coil sensors also act as torque rods for part of the orbit. Noise cancellation algorithms enable scientific grade magnetic measurements from the system without needing a sensor boom.

Abstract: The present invention relates to a lightning protection device comprising a ground plate having a plurality of parallel grooves machined therein. Each of the grooves has spaced apart, sharp edges for bleeding electrical discharges from a lightning strike to ground. The ground plate may be connected to an air terminal secured to a structure or a marine vessel via a down conductor. The ground plate may be buried in the ground or may be joined to a structure, such as the hull of the vessel.