Where are people placing their space stations and why?

[cantab]

I don't have any trouble with it; although a low circular orbit has a higher speed relative to the ground, it's actually a lower orbital velocity than a high orbit.

No...it's a higher orbital speed for a lower circular orbit. But I don't think it makes that much difference since the applicable distances are from the primary's centre, so eg a 150 km Kerbin orbit isn't anything like twice the size of a 75 km one.

[TimePeriod]

I only use space stations on Minmus/Mun to have a science collection point. Allows me to reuse my (now) expensive science-parts, refuel my lander and exchange crew once a fuel-tanker comes around.

[Wanderfound]

No...it's a higher orbital speed for a lower circular orbit. But I don't think it makes that much difference since the applicable distances are from the primary's centre, so eg a 150 km Kerbin orbit isn't anything like twice the size of a 75 km one.

Get into a low orbit. Accelerate. You'll end up in a higher orbit. Higher = faster. Higher is slower relative to ground but faster relative to a universal reference frame.

[Wallace]

I currently only have stations at Mun, Minmus, Duna and Jool. No kerbin stations, but when I did I had a fuel station at 73km and stations at 150km and 300km

[MockKnizzle]

Get into a low orbit. Accelerate. You'll end up in a higher orbit. Higher = faster. Higher is slower relative to ground but faster relative to a universal reference frame.

Kind of, but not really. Higher = more orbital energy, certainly. But orbital energy is dependent on both size (the semi-major axis of the orbit) and the velocity of the spacecraft, via the vis-viva equation.

If you burn from a low circular orbit, you are now in an elliptic orbit with a periapse at the altitude of your original orbit. You are going faster than the circular speed at that altitude, but later on at apoapse you will be traveling slower than circular speed. Saying "higher = faster" is missing the important point that orbital speed of a non-circular orbit changes.

Furthermore, saying "higher = faster" is simply not true in the case of circular orbits, where orbital speed is simply the circumference of the orbit divided by the period. Orbital speed in this case is proportional to sqrt(1/radius), and clearly decreases as the radius gets larger.

[Volcanix]

I've just started a new sandbox save and placed the core for my KSS (Kerbal Space Station, creative, right?) in a 75km equatorial orbit around Kerbin. I put it that low because I wanted that also little ships could fly up there easily, because higher orbit also means more ∆V to get there. Even if it's not much, it can make a difference. Basically, you can orbit any planet without an atmosphere as low as you want, as long as you don't fly into a mountain. What I mean by that is that when your "to-orbit-planet"'s highest point is at 200m, you can basically orbit at 201m or a bit more, depending on the height of your ship. I hope I helped you^^

Volcanix.

[Miro Beero]

Do you guys use the kethane pack to refuel your stations, or do you lug all your fuel all the time to your stations from kerbal?

[Piper]

I seem to be the exception, with having a station in KSO. I built a "deep space telescope" that I wanted to be easily accessible to astronauts, but far enough up that Kerbin wasn't blocking half the sky. As such, I went with KSO. however, I'm thinking of moving the station to the L4 Mun lagrange point. With a Munar fly-by, it's just as easy to get to, and there's even more of the sky open to me.

[cantab]

Do you guys use the kethane pack to refuel your stations, or do you lug all your fuel all the time to your stations from kerbal?

I did a bit with kethane, but never really used it for anything further. In the pre-money days there wasn't much point to kethane in Kerbin's SOI because you can just launch fuel any time. Now we have finances I don't know how the economics stack up, but of course one must remember kethane is finite.

[AlexanderB]

I had one at like.. 7.1k above the mun*, polar orbit. It was so cool to see the surface race by, sometimes close enough to nearly touch it, and docking to it was a scary proposition. Then it got eaten by timewarp.

*I looked up the tallest mountain and rounded it up, but I think it wasn't enough..

My usual stations are 100-ish, this leaves the 70 to 80 region free to "catch up", and is low enough to serve as a refueling point with maximum oberth effectiveness.

[Pecan]

From my tutorial:

The big question about orbital spacestations is where to put them. Low, 75km, orbits make them easy to reach for

vehicles that are launching but leaves no room beneath them for a phasing orbit, if one is required for rendezvous. A

higher, 600km, orbit provides an efficient departure-point for interplanetary trips but is harder to reach for launching

vehicles and leaves, if anything, too much work to be done by those that are de-orbiting. My preferred 'traffic control'

zones use the following orbital heights (which, as always, you should feel free to ignore):

75km – launch/de-orbit vehicles and low phasing orbit

150km – low rendezvous/parking orbit

250km – space-station orbit

350km – high rendezvous/phasing orbit

600km – interplanetary parking orbit

[Barefoot Friar]

I put mine at 1434Km. I tried one at 100km, but that was so close and moving so fast that I could never dock with it. I expended an entire large tank of RCS trying to dock with it one day, and got so frustrated that I deleted it and built a new one at a higher orbit. Sooooo much easier!

It does take more dv to get there, but I decided that wasn't a big deal. Fuel is cheap in sandbox. I haven't even played .24 yet, so I don't know if I would do it again there in career mode or not. We'll see. (I'm trying to buy a new computer, so it'll be a while.)

[merendel]

Do you guys use the kethane pack to refuel your stations, or do you lug all your fuel all the time to your stations from kerbal?

depends on the game, sometimes yes sometimes no. If I do have kethane I'm more likely to send along a mining/refining setup than to send fuel shipments to anywhere out of kerbin's SOI. Only times I'm likely to do much kethane mining in the kerbin system itself is if I'm also runing extraplanetary launchpads and make an orbital shipyard out at minmus.

Its possible to get orange tanks into orbit mostly on solid fuel so its not all that expensive. Send it up, discard the solids and have a smallish upper stage that finishes orbital insertion burn and gets it to the fuel depot. a few spacetugs in your fleet and you can lug the tanks from the depot to any SOI that needs it.

[Pecan]

...I expended an entire large tank of RCS trying to dock with it one day...

Docking school - go!

Seriously? A LARGE tank? Docking even big ships should only take less than 20 units of monopropellant once you've practiced, which is why you see so many people relying just on what's in the command pod. The orbital speed of what you're docking with/to shouldn't matter at all, it's all about relative velocity.

On a different slant - around Mun I tend to use a 50km orbit, to allow for a 10km phasing orbit below the station.

[cantab]

It is true that higher orbits are easier to dock in though, and more tolerant of distant initial rendezvous, because there's less curvature. The extreme case is intercepting asteroids in solar orbit - you can quite happily match speeds and burn towards the target from a couple of hundred km out.

Also, I remembered something: for a fuel depot, a higher orbit can reduce the onward delta-V requirement. I'm not sure what the ideal height is for that.

[Pecan]

Less curvature is true, but you either rendezvous or you don't. The reason tutorials recommend orientating docking ports North-South is to overcome the problems with fast orbital periods. Rendezvous is the real issue though - if you can get to a relative stop within 1km or so you should be able to dock with minimal fuel within 5 minutes.

600km is recommended for some interplanetary transfers, IIRC, but as noted in my earlier post, I don't find that a good place to put a space-station.

[Uncle Mort]

I have a low (85km) orbit station for personnel transfer as my SSTO rocket cannot reach any higher and still retain enough fuel to rendezvous and deorbit safely. Main station is at 300km and there's a Mun station at 80km.

[nadreck]

In 0.24.2 I have what I call Tank Farm in 90km equatorial orbit:

I have a shuttle called Fuel Train that goes back and forth to a tank and spare lander in an approximately polar Munar orbit, it brings my science modules back and I put a Kerbonaut with samples and EVA reports on board too:

And here is my LowGee NSUV Mk1.1 and a spare that along with another tanker module acts as a station and emergency rescue craft at the MUN, they stay in polar orbit the NSUV (Nuclear Science and Utility Vehicle) can generally make two landings on the Mun per fueling though I could only do one when I landed at the north pole (I had to translate a lot to find relatively flat ground to land on).

Note that my Fuel Train is powered by the LowGee NSUV Mk1 (it was missing lights and was, after two Munar landings, up graded with the NSUV Mk1.1) Note the 4 science modules on each lander in the picture above. They have their own chutes and return to Kerbin independently after being brought to LKO and the Tank Farm.

[SelectHalfling0]

80 Km. Why?

70 Km: orbital insertion stage drop off point

90 Km: interplanetary ship construction zone

100 Km: Classified Vehicle testing grounds

[samstarman5]

With docking ports stronger than when they were first introduced, it can be rather practical to build a station in low orbit, and then bring it up to a higher, more stable orbit. It would definitely be advisable to have it symmetrical if changing orbital altitude is planned.

I tend to go for 100km, myself, but there are definite merits for going higher as you need fewer adjustments when making approach and docking maneuvers.

[Dispatcher]

My stations (and bases) so far are just renamed craft that have failed to return to Kerbin.

[montyben101]

125km is the orbit for all my satellites and stations as i can time warp 100x

[Raptor9]

My stations (and bases) so far are just renamed craft that have failed to return to Kerbin.

LMAO! Mitch Kerman: "Well, I was stranded, but now I live here. I've greatly improved my situation."

In Sandbox Mode, I went nuts with stations. But in the latest career mode, I've had to justify expenditures. Like some previous posts in this thread, I've put a small science outpost around Minmus to keep to/from costs down. I was able to completely explore Minmus in three expeditions: 1) Assemble the outpost, 2) Bring a mono-powered lander and explore 4 of the 8 biomes, 3) Explore the remaining 4 after bringing back some more monopropellant for the lander.

Other uses in Kerbin orbit to keep costs down would be a transfer station with a fuel depot. SSTO arrives from the planet surface for crew transfer to an interplanetary/moon ship; you get the reusability advantages of not just your SSTO, but you don't have to keep launching orbital capsules if you can just refuel them for the next expedition. The biggest costs in this case would be getting regular trips of fuel lifters to the station. That's a thread on it's own, and there are several.

[gc1ceo]

Update:

Added a Mun station at 8k, removing my 15k one and turning it into a makeshift Kerbol orbiting observatory.