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How do spacecraft reach Lagrange points? First things first: Spacecraft don't go to the various Lagrange points of interest. They instead go into pseudo orbits about those Lagrange points. How do spacecraft reach Lagrange points? Either fuel efficiently, but slowly, or by brute force. Consider the Earth-Moon Near Rectilinear Halo Orbits (NRHOs) that are ...


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Supplemental answer to @Schwern's answer The GIF below shows SOHO traveling out to it's halo orbit around Sun-Earth L1. JWST will do something that looks similar, but towards Sun-Earth L2. Why does the trajectory nicely dovetail into the halo orbit? This is really interesting. If you first put the spacecraft in its halo orbit, but just a tiny bit too close ...


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As I understand, to reach a Lagrange point the spacecraft would need to slow down. If it's launched from the Earth it does not need to use propellant to slow down. NASA explains this in its article about the James Webb Space Telescope which will orbit the Earth-Moon L2 point. It will take roughly 30 days for Webb to reach the start of its orbit at L2, but ...


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Are bicomplex numbers including tessarines ever used in spaceflight (as an alternative to quaternions)? Without the parenthetical remark, the answer is "I don't know". But with that parenthetical expression, the answer is all-caps "NO". Unit quaternions are used in space exploration precisely because they map nicely to rotations in three ...


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See also answers to How much does the rotation of the Earth affect re-entry and could we go against it? When things land on Mars what fraction of their velocity do they remove propulsively? Difference in atmospheric entry for Earth and Mars Any attempted Mars landings without an ablative-type heat shield? (asked just now) Answers to What aspects of reentry ...


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Spacecraft Maneuvers as Intellectual Property? Wow! I was thinking the same thing until I realized every orbital maneuver patent I was looking at was actually a process or method patent of the underlying calculations and software. Do we see patents on the use of actual orbital maneuvers themselves in which the patent holds regardless of the algorithm used ...


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There is always a benefit to entering a planet's atmosphere with matching rotation. In the case of Earth, the difference is a rather huge 920m/s effective airspeed between reentering prograde or retrograde. With Mars the effect is smaller but still strong, at some 485m/s difference. Even on the Moon it makes a difference, but so small as to be almost ignored....


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Space craft will tend to enter orbit counter clockwise as viewed from the northern hemisphere. This is due to the fact that most objects in the solar system orbit and rotate this way with the exceptions of Venus, Uranus and a few asteroids. Moving in the direction of rotation will therefore reduce the required velocity loss where as entering orbit clockwise ...


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As long as your panels produce electric energy - as under solar flux - you can use that energy to produce thrust, e.g. either using an ion engine or (as long as you are within a strong magnetic field like that of Earth or of Jupiter) an electrodynamic tether. If solar flux is too low to produce electricity they became dead mass (and could be consumed as ...


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This paper about attitude control in VLEO using aerodynamic surfaces, provides lots of useful data, and glimmers the possibility of such a "cold" atmospheric entry. Maybe taking advantage of the square cube law could become the key, and if a 1U cubesat is too big to keep the angle of descent small enough so that temperature and velocity stay ...


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In theory, the photon drive exists, and has infinite ISP but low energy efficiency. Any electrical power can be used to provide thrust. But in practice, solar panels make better solar sails than photon drive power sources.


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Partial answer based on the constraints the question appears to have. Some solutions would not be considered practical by today's standards, but this doesn't appear to be asking for only practical solutions, as "no bases on the way" sounds like interstellar travel. You can't buy these at Spacecraft-R-Us. It is under ample solar flux Use the solar ...


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