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Fictional Planet has a gravity of approximately 0.68g

Geostationary orbit of said fictional planet is approximately 32,000 km above the surface according to online calculator.

Spacecraft capable of approximately 3g of constant acceleration (for purposes of this discussion, ignore normal requirements for fuel and/or reaction mass).

I presume that the spacecraft will also need time to DECCELERATE, but I have no idea how much affect 0.68g of planetary gravity will have on this.

Given this information, approximately how long after launch would it take for the spacecraft to reach a space station in geostationary orbit?

White76Knight
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    Worldbuilding stack exchange might be better for purely hypothetical questions. – Organic Marble Oct 05 '19 at 15:51
  • How exact a value are you looking for? Assuming no atmosphere to deal with and no time spent matching orbits, flight time's probably going to be under 40 minutes. – notovny Oct 05 '19 at 17:33
  • What are the radius and rotational period of said planet? That will determine how fast you’re going upon launch, which will also determine how much more velocity you need to get to that orbit. Also, what is the orbital velocity at that altitude? Would you mind throwing in a J2 harmonic perturbation parameter to the description of your planet? – Paul Oct 05 '19 at 21:23
  • @Paul that's a good point about the radius and period. I suppose one could assume that average density was the same as Earth's as an initial guess, then the planet's radius and period could be calculated (I think). But it might be better to find out what the OP typed into the on-line calculator, so... – uhoh Oct 06 '19 at 00:05
  • @White76Knight it would be better if you shared all of the information. Why not add a screen shot of the on-line calculator's input or just include all of the input values that you supplied? I think the surface gravity and orbit size alone are not enough to answer the question. See comments above. – uhoh Oct 06 '19 at 00:07
  • The value does not need to be exact, just exact enough that I don't say something like, "yeah we made the shuttle trip up to the station in about an hour" or whatever, when it should have been like two days or something. That said, Radius of the planet is 4305 km. Rotational period is approximately 35 earth hours. Atmospheric density is approximately 0.86 that of earth. And that J2 harmonic perturbation? I, uh, have no idea what that is. – White76Knight Oct 06 '19 at 01:39
  • Perhaps the OP is working off the assumption of a standard gravitational parameter that is 0.68 times that of earth, rather than simply the surface gravity being 0.68 times that of earth (which wouldn’t really be enough to provide an answer). It’s probably safe to assume a J2 of zero, along with all other harmonics, for simplicity. – Paul Oct 06 '19 at 02:01
  • Surface gravity is 0.68g. Is that what you'd need? If the standard gravitational parameter is what you're after, what other data would you need to derive that? Planetary mass is about 0.30 that of earth, and density is approximately 0.97 that of earth, if any of that stuff helps. – White76Knight Oct 06 '19 at 02:08
  • My question was put on hold because it was unclear what I was asking? I am genuinely unsure how I could make this question any clearer. I have provided every piece of information that I thought might be necessary or relevant, but just in case I overlooked something, I even asked what additional information was needed but received no further reply. By all means, please tell me what I have overlooked and I will be happy to provide more data. – White76Knight Oct 07 '19 at 16:35

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