NASA Deep Space Navigation
NASA Deep Space Navigation Techniques The Three Parts of Navigation Spacecraft navigation comprises three main aspects: Designing a reference trajectory which describes the planned flight path of the spacecraft; this is the task of mission design. Keeping track of the actual spacecraft position while the mission is in flight; this is the work of orbit determination. Creating maneuvers to bring the spacecraft back to the reference trajectory when it has strayed; this is the area of flight path control. A spacecraft is always orbiting something. On the launch pad, it is orbiting the sun along with the earth. A spacecraft on its way to a distant planet is following its own orbit about the sun. Spacecraft that have landed on a planet or other body are still orbiting the sun. Some spacecraft are orbiting planets or other bodies, while those bodies themselves are orbiting the sun. A fe...