Study of Regions of Stable Orbits and Natural Escape and Capture Routes in the Sphere of Lunar Influence
- Paper number
IAC-07-A3.I.A.02
- Author
Dr. Cristiano Fiorilo de Melo, INPE, Brazil
- Coauthor
Prof. Elbert E.N. Macau, Instituto Nacional de Pesquisas Espaciais (INPE), Brazil
- Coauthor
Dr. Othon Winter, Brazil
- Coauthor
Dr. Ernesto Vieira Neto, Brazil
- Year
2007
- Abstract
Several space agencies recently announced their intention to intensify lunar exploration activities, including manned missions, as well as the establishment of permanent bases close to the lunar poles. In accordance with this trend, we examined the sphere of lunar influence, which has a radius of some 60,000 km, considering the restricted three-body and the four body problems. Next, we mapped out regions of stable orbits around the Moon with inclinations between 0 and 180o. For inclinations between 60º and 120º, there are regions of stable orbits with semi-major axes varying between 1,750km and 10,000 km and eccentricities between 0 and 0.6. These regions can be useful for maintenance of constellations of communications satellites, since from some of points close to the Southern lunar pole, for example, the Earth can be below the horizon for up to 3 weeks each month, blocking radio signals. The sphere of lunar influence also presents regions of paths that escape after going around the Moon for some time, and are later recaptured by the lunar gravitational field through the Lagrangian L1 and L2 points of equilibrium. These paths define natural escape and capture routes and exist for any inclination between 0 and 180º. Thus, they can be useful for low cost insertion of many different kinds of vehicles in high inclination lunar orbits. In this study, we also investigated some maneuvers to acquire these paths.- Abstract document