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1

To me the term jump is defined as a phsyical movement that implies a somewhat impulsive force acting against gravity to move an object and then subsequently the object returns to a datum plane under the return influence of gravity. A lateral velocity component could be included so the return point is at some distance from the starting point. In the ...


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It is not mandatory that the two vessels have zero relative velocity, but it would make the operation more controlled (and therefore less exciting). Having vessels in close proximity with significant relative velocity risks collision so would only be likely in uncontrolled or emergency conditions. If your scenario involves relative velocity, the jump ...


2

(An addition to answers posted already, from Is it possible to refuel the James Webb Space Telescope?): A: That depends on the JWST having its tanks/plumbing/ports accessible to a robot. (from what I have seen, I think it is a no..) IF it does then...yes-ish: Northrop Grumman's MEV - Mission Extension Vehicles - have demonstrated the ability to physically ...


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Your idea that "no air would be able to enter the nozzle because the vehicle is moving faster than the speed at which air would be sucked in" is inaccurate. But the vehicle speed is irrelevant here. The answer is pretty well-summarized in the top answer here as someone else linked, but to re-state it: Vacuum-optimized engines are not operated in ...


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I found out today that in fact Nasa have built in refueling points onto the JWST in order to refuel should the need or want arrive. Via a "Robotic refueler" was the term used. Not direct evidence, but this seems more likely after reading Ars Technica's All hail the Ariane 5 rocket, which doubled the Webb telescope’s lifetime Because ten years ...


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Clip on thruster units already exist, at least for geostationary orbit. The Mission Extension vehicle has flown twice, most recently in 2020. It operates by mechanically coupling to a suitable engine nozzle and is otherwise independent. The challenges in using an off the shelf MEV for JWST is that the speed of light latency would force more autonomy on the ...


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Your « how do spacecrafts know ... ?» question begs the prerequisite one: do we need them to know [in order to correct their orbits]?. In other terms, do we need them to autonomously determine (a) how they are oriented and (b) where they are (in a given reference frame, at any given time)? It is quite true (and somewhat intuitive) that we do not wish to, for ...


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Orientation is easy; it's in your user name. Star trackers are widely used to sense orientation. Rate gyros are often used to track orientation between star tracker readings. There is a potential issue with using rate gyros, which is that they measure rotation rate rather than orientation. Since the measurements aren't perfect, the estimated orientation ...


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