Mission Design of an Aperture-Synthetic Interferometer System for Space-Based Exoplanet Exploration

In recent years,exoplanet detection has become the technological frontier in the field of astronomy,because it provides evidence of the origin of life and the future human habitable exoplanet.Deploying several satellites to form an aperture-synthetic interferometer system in space may help discover“another Earth”via interferometry and midinfrared broadband spectroscopy.This paper analyzes a space-based exoplanet exploration mission in terms of the scientific background,mission profile,trajectory design,and orbital maintenance.First,the system architecture and working principle of the interferometer system are briefly introduced.Secondly,the mission orbit and corresponding transfer trajectories are discussed.The halo orbit near the Sun-Earth L2(SEL2)orbit is chosen as the candidate mission orbit.The low-energy transfer via stable invariant manifold with multiple perigees is designed,and the proper launch windows are presented.A speed increment less than 10 m/s is imposed for each transfer to achieve the insertion of the halo orbit.Finally,the tangent targeting method(TTM)is applied for high-precision formation maintenance with the whole velocity increments of less than 5×10^(−4)m/s for each spacecraft when the error bound is 0.1 m.The overall fuel budget during the mission period is evaluated and compared.The design in this paper will provide technical support and reliable reference for future exoplanet exploration missions.

A Review of Orbital Mechanics for Space-Based Gravitational Wave Observatories

The confirmation of gravitational waves in recent years has set off a new upsurge of exploring the extreme interactions critical to the origin and evolution of stars,galaxies,and the universe.The detection of gravitational waves in space is expected to cover the largest number and the greatest variety of gravitational wave sources,which is more compelling and valuable than the initial detection on the ground.Orbital dynamics and control are the keys to realizing the detection of gravitational waves in space.This paper reviews the orbital mechanics for space-based gravitational wave observatories.The principle and typical gravitational wave observation mission concepts are first introduced and classified summarized.Then,the orbital mechanics of the space-based gravitational wave observatories in different spatial locations are reviewed.On the basis of the characteristics of different observatories,2 groups of methods related to the observatory configuration design and optimization are summarized:the constellation configuration design and optimization method similar to the geocentric configuration and libration point configuration,the formation design and optimization method similar to heliocentric configuration.The prospects of space-based gravitational wave observatories are finally put forward,which shall provide a reference for future research on space-based gravitational wave observatories.