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halo orbit 'tilt' has nothing to do with coriolis but is caused by the object speeding up and slowing down as it orbits the sun. In a Sun-Earth L2 halo orbit the object is ALWAYS orbiting the sun in the same direction as the earth at an AVERAGE orbital velocity equal to earth's. HOWEVER... the object in halo speeds up and slows down a tiny bit so that it is ...


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Partial answer.. perhaps more of a comment... downvote expected... In theory the answer could be yes. It relates to the concept behind the JWST successor of soughts, the LUVOIR set for launch in 2039. Large Ultraviolet Optical Infrared Surveyor is effectively composed of two separate spacecraft flying in close formation. This brings two main benefits: This ...


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It could be, but the main challenge is going to be executing burns with thrusters that aren't aligned with the center of mass of the tug-JWST pair. Assuming the goal is to keep the sun behind the sun shield at all times, the tug will need to be able to perform translation maneuvers in a few directions without JWST changing its attitude (except for the yaw ...


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Nice descriptive question with the illustrations! I'll look forward to a more educated answer, but here are my two-cents: [Edited in response to @Woody's comments] Looking at the definition of a Halo orbit, it seems to be quite specific and involves all three dimensions and is not a small perturbation: "In 1973 Farquhar and Ahmed Kamel found that when ...


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The Wind spacecraft has been orbiting the Earth-Sun L1 point since roughly May 2004. Originally it was put into a Lissajous orbit but was recently moved into a halo orbit in late 2020. Typically, Wind uses ~0.13-0.20 kg of fuel per maneuver and four maneuvers per year (it had ~36 kg remaining as of December 16, 2021, i.e., ~45-60 years of fuel left). For ...


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The short answer is no. Lagrange points are saddle points, in topological terms. They are only quasi-stable, but not actually stable. Solar radiation pressure is enough to cause a nutation and precession of the Wind spacecraft's spin axis over the course of a year (forms an ellipse on a polar graph with a diameter of about 1 degree). That force alone ...


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It seems that they do. As @Diane noted in a comment, this paper (PDF freely available) discusses Lissajous orbits and approximation of their invariant manifolds: Europa Lander Trajectory Design Using Lissajous Staging Orbits Abstract: Lissajous orbits and approximation of their invariant manifolds are used to generate landing trajectories to the surface of ...


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Besides what's already been mentioned -- eclipses have a risk associated with them. Basically, if the spacecraft doesn't know that this is a planned eclipse, and the systems kick in to try to "find" the sun, this will put the spacecraft into a roll that it might not recover from. (because it's no longer getting solar power to operate). This is how ...


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