Designing rendezvous missions with mini-moons using geometric optimal control

Detecting Earth’s temporarily-captured natural satellites—Minimoons

“…Under these assumptions our calculations suggest that there are about 1, 5 and 30 TCOs respectively on the sky plane at any time which suggests that this type of mission could provide a steady stream of TCOs for ground-based physical characterization (rotation state, colors and/or spectra) or even opportunities for rendezvous, retrieval, or resource studies and utilization (e.g. Chyba et al 2014). Actual TCO surveys in the IR from L1 would need to avoid surveying too near the Earth and Moon but detailed modeling of their performance is beyond the scope of this work even though the prospect of TCO discovery with this type of mission is promising.…”

“…The preferential detection of the long-lived TCOs has implications for spacecraft TCO rendezvous missions because they have the advantage of being accessible by spacecraft for years after their discovery (Chyba et al 2014).…”

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We present a study on the discoverability of temporarily captured orbiters (TCOs) by present day or near-term anticipated ground-based and space-based facilities. TCOs (Granvik et al 2012) are potential targets for spacecraft rendezvous or human exploration (Chyba et al 2014) and provide an opportunity to study the population of the smallest asteroids in the solar system. We find that present day ground-based optical surveys such as Pan-STARRS and ATLAS can discover the largest TCOs over years of operation.

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Recent Advances in Celestial and Space Mechanics

“…A consequence is that statistically, at any moment there is a one meter diameter TCO orbiting the Earth. The advantages presented by the TCOs for space missions have been discussed in several papers [1,2,3, 4] and we will not repeat the arguments here, but clearly it is what motivates our work. In particular, their vicinity to the Earth-Moon system is very attractive and their energy typically will help minimize the amount of thrust required by the spacecraft to reach them.…”

“…In order to solve the optimization problems associated with our mission, we use indirect shooting methods [3,4,5,12]. The main difficulty of these methods is the initialization of the algorithm and existence of numerous local minima.…”