Eclipse avoidance in TianQin orbit selection

Abstract

In future geocentric space-based gravitational-wave observatory missions, eclipses due to passing through the Moon's and Earth's shadows can negatively impact the sciencecraft's thermal stability and steady power supply. The occurrence should be reduced as much as possible in orbit design. In regard to TianQin's circular high orbits, we tackle the combined challenges of avoiding eclipses and stabilizing the nearly equilateral-triangle constellation. Two strategies are proposed, including initial phase selection and orbit resizing to 1:8 synodic resonance with the Moon, where the latter involves slightly raising TianQin's preliminary orbital radius of $1\times 10^5$ km to $\sim 100900$ km. As the result, we have identified pure-gravity target orbits with a permitted initial phase range of $\sim 15^{\circ }$, which can maintain eclipse-free during the 3+3 month observation windows throughout a 5-year mission started in 2034, and meanwhile fulfil the constellation stability requirements. Thereby the eclipse issue for TianQin can be largely resolved.

7 pages, 7 figures, to match the published version

References in corpus (8)

• The TianQin project: current progress on science and technology
• Science with the TianQin Observatory: Preliminary results on Galactic double white dwarf binaries
• Science with the TianQin observatory: Preliminary results on stellar-mass binary black holes
• Optimizing orbits for TianQin
• Science with the TianQin observatory: Preliminary result on extreme-mass-ratio inspirals
• Preliminary study on parameter estimation accuracy of supermassive black hole binary inspirals for TianQin
• Impact of orbital orientations and radii on TianQin constellation stability
• gLISA: geosynchronous Laser Interferometer Space Antenna concepts with off-the-shelf satellites