Interplanetary Motion - The Navigation of Spacecraft
Abstract
In this essay the problem of navigation of spacecraft, from the Earth to another planet in the solar system is covered. The problem is found to be initially complex. However, by splitting the problem into orbital injection, midcourse and capture, each dominated by different gravitational fields (the Earth, Sun, and target planet respectively), it is simplified greatly. Each of these stages is then considered separately, the first dealt with by considering the escape velocity, and introducing the accelerometer as a means of achieving this. The second stage is considered by means of an orbit around the sun, introducing the Hohmann orbit, which involves the least possible energy. Then the final stage of orbit is considered. Finally the slingshot effect is considered, as a means to reduce the energy involved further, finding that momentum can be transferred from a planet to the spacecraft, and the application of this technique, by linking together several Hohmann orbits is considered.