1306.5333 (Joseph W. Gangestad et al.)

A High Earth, Lunar Resonant Orbit for Lower Cost Space Science Missions    [PDF]

Joseph W. Gangestad, Gregory A. Henning, Randy R. Persinger, George R. Ricker

NASA astrophysics robotic science missions often require continuous, unobstructed fields-of view (FOV) of the celestial sphere and orbits that provide stable thermal- and attitude-control environments. To date, the more expensive "flagship" missions use the second Earth/Sun Lagrange point (L2) approximately 1.5 million km from the Earth outside the orbit of the Moon or a "drift away" orbit to distances >10 million km. A High Earth Orbit (HEO) offers similar advantages with regard to continuous, unobstructed FOV and a thermally stable environment with minimal station-keeping requirements. The "P/2-HEO," an orbit in 2:1 resonance with the orbit of the Moon, also provides the opportunity for data downlink at orbit perigee distances close to the Earth allowing for lower-cost communications systems. The P/2-HEO oscillates on the order of 12 years and trades orbit eccentricity for orbit inclination. This orbit variability can be selected for optimum spacecraft performance by proper choice of the conditions using a lunar flyby for gravitational assist. The lunar flyby and the shorter distance for science data downlink offer lower cost astrophysics missions the advantages of the more expensive L2 or "drift away" orbits.

View original: http://arxiv.org/abs/1306.5333