DescriptionThe Sun-Earth L5 point is growing in interest as an outpost for a space weather observatory. It allows observations of solar regions that are about to rotate towards Earth, enabling advanced warnings for Earth-approaching solar storms. While missions to L5 using chemical or ion propulsion have been (and still are) under investigation, this paper proves solar-sail technology as a viable propulsion method to reach the L5 region. By hybridizing several techniques (genetic algorithm, multiple shooting differential correction, and continuation), locally time-optimal transfers are obtained in the circular restricted three-body problem. To increase the viability of these transfers, the performance of solar-sail technology for small satellites currently under development at NASA Langley Research Center is assumed. Two mission scenarios will be considered where the spacecraft is either launched from Earth as a secondary payload on a primary mission to L1 or on a dedicated launch. Furthermore, both classical and solar-sail displaced planar Lyapunov orbits around the L5 point will be targeted. For a conservative lightness number of 0.02, the ride-share option enables a transfer time of 658 days to a classical planar Lyapunov orbit, which can be reduced to 571 days for the dedicated launch scenario. For a larger lightness number of 0.025, the transfer times for all cases considered reduce, on average, by 11%. Finally, the fastest transfers are obtained for targeting the family of classical planar Lyapunov orbits. Targeting their solar-sail counterparts increases the transfer time by, on average, 18%. The proposed hybridization of techniques appeared to be a robust and versatile approach to finding solar-sail pathways to the L5 point that can be easily adapted to any future updates to the mission scenarios considered in this paper.
|Period||31 Jul 0030|
|Event title||5th International Symposium on Solar Sailing|
|Degree of Recognition||International|