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Abstract Using data from Gaia DR3, we construct a sample of 14,791 gravitationally bound wide pairs in which one of the components is an unresolved binary with an astrometric orbital or acceleration solution. These systems are hierarchical triples, with inner binary separations of order 1 au, and outer separations of 100–100,000 au. Leveraging the fact that the inner binary and outer tertiary should have nearly identical parallaxes, we use the sample to calibrate the parallax uncertainties for orbital and acceleration binary solutions. We find that the parallax uncertainties of orbital solutions are typically underestimated by a factor of 1.3 atG> 14, and by a factor of 1.7 atG= 8–14. The true parallax uncertainties are nevertheless a factor of ∼10 smaller than those of the single-star astrometric solutions for the same sources. The parallax uncertainties of acceleration solutions are underestimated by larger factors of 2–3 but still represent a significant improvement compared to the sources’ single-star solutions. We provide tabulated uncertainty inflation factors for astrometric binary solutions and make the catalog of hierarchical triples publicly available.
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Minimum-Fuel LEO-to-MEO Orbit Transfer Using Adaptive Gaussian Quadrature Collocation
A numerical optimization study of a minimum-fuel LEO-to-MEO orbital trajectory trans- fer is solved using a bang-bang and singular optimal control (BBSOC) method with multi- domain Legendre-Gauss-Radau quadrature collocation. Modified equinoctial elements are used to avoid singularities that occur in orbital elements. The time, t, state components, (p, f,g,h,k,L,m), and control components, (ur,ut,un,T) are optimized in this one phase prob- lem where seven cases of the initial thrust acceleration values are considered. The structure of the thrust was not assumed, therefore the optimizer determined the number of switch points. The solutions were categorized as partial and multiple revolution optimal trajec- tories. The initial thrust accelerations considered for the partial revolution solutions are s0 = 1.0206 × 100, 5.1029 × 10−1, 1.0206 × 10−1, 5.1029 × 10−2 AU. Furthermore, as the ini- tial thrust acceleration decreased, the final mass decreased while the total time thrusting increased. The initial thrust accelerations considered for the multiple revolution solutions are s0 = 1.0206 × 10−2, 5.1029 × 10−3, 1.0206 × 10−3 AU. Furthermore, as the initial thrust acceleration decreased, the final mass increased while the total time thrusting increased. An in-depth study was completed for the cases of s0 = 1.0206 × 10−1, 1.0206 × 10−3 AU, where the final mass was [0.6683, 0.5991] MU and the total time thrusting was [4.0305, 487.3276] TU.
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- Award ID(s):
- 2031213
- PAR ID:
- 10382623
- Date Published:
- Journal Name:
- AIAA SciTech Forum
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.2514/6.2022-2274
