Solar-Sail Pathways to the Sun-Earth L5 Point

Activity: Talk or presentationTalk or presentation at a conference


The 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.
Period31 Jul 0030
Event title5th International Symposium on Solar Sailing
Event typeConference
Conference number5
LocationAachen, Germany
Degree of RecognitionInternational