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Circular orbits at different altitudes require different speeds, so if you start with a radial separation, the spacecraft and station will tend to drift further apart unless they accelerate themselves radially to close the distance. The effect is small at small distances, larger at long distances. To a first approximation, the separation is the difference ...


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Welcome to Space stack exchange. This is a part of launch window analysis and I'd recommend using that as a search term. The simplest answer is "a bit more than 180 degrees". This is for the situation where the launch site is on the equator and the target satellite is geostationary rather than inclined geosynchronous orbit. Imagine that the ...


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The technical and organizational causes of the Gemini IV station-keeping failure are discussed in this conference paper. John Goodman, “A Cautionary Tale of a Secret, a Small Team, an Accelerated Schedule, and the Gemini IV Station-Keeping Failure,” 43rd Annual AAS Guidance and Control Conference, Breckenridge, CO, January 30 to February 5, 2020. paywalled ...


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The basic idea is that if you can get there within a small fraction of the orbit, the orbital dynamics do not matter at all. You are close enough that the two spacecraft will essentially be in the same orbit. As a low orbit is 90 minutes or so, if you can get there in 5 minutes you don't have to worry about what the gravity does. If you can get much ...


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OMS2 is the burn of the Space Shuttles' Orbital Maneuvering System that circularizes the orbit after launch. After it the shuttle was in the same orbital plane as the ISS, but some distance behind. To catch up with the ISS, the orbit was slightly lower (~ 80 km) and therefore faster. The OMS2 Phase Angle tells how far behind the shuttle was. In other words, ...


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Many sources. (eg this one) mention the samples orbiting Mars in a "basketball-sized" container until collected by the Earth Return Orbiter. I haven't seen any authoritative ones saying it's also shaped like a basketball.


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Okay, so I've been super jazzed about this same idea for a while now, so I can't help but chime in. For starters, the problems with rendezvous are quite important, as already stated-- a second off can mean kilometers, etc, etc. Having said that, we've seen computer controlled rockets do perfect suicide burns; not every time, there's still room for ...


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