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I'm playing career mode with RemoteTech. A major task I'm facing is deploying a network of communication satellites in keostationary orbit. As I understand it, three spaced out evenly across the orbit would be the ideal configuration.

Putting satellites into KSO is easy enough, but how do I go about the spaced out evenly part? Should I simply launch them 2 (6-hour orbit divided by 3 satellites) hours apart, or are there other methods?

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The best approach, in my opinion, is to launch all three satellites on the same launcher. Each satellite will also need to have enough delta-V to finalize its own orbit.

First step is to launch your rocket into a geosynchronous transfer orbit (GTO). It doesn't really matter what your perikee is at this stage, but your apokee should be at geosynchronous altitude (2,868.75 km).

The second step is to raise your perikee such that your orbital period is 1/3 or 2/3 that of a GEO orbit (2 or 4 hours).

Finally, you're going to put each of your satellites into their final orbit, one at a time. I prefer to wait an orbit after raising the perikee, but it's not entirely necessary. Detach the satellite, and use its apokee motor to finalize its orbit. Switch back to the launcher, wait an orbit, and repeat with the next satellite.

Getting your orbital altitudes aren't as important as getting the proper orbital period. If the periods aren't exact, your satellites will start to drift out of formation. If your satellites aren't in formation, simply raise or lower their orbits for a few revolutions until they're in place.

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  • I'm afraid I don't have the technology for that quite yet. What should I do if I can only launch one at a time?
    – Pvt. Grichmann
    Commented May 9, 2015 at 19:27
  • In that case, put the first one up and in its proper orbit, then put the other two up in staging orbits with periods of around 5 hours and 45 minutes, and then, when the time is right, put each of them in their proper orbit.
    – MBraedley
    Commented May 9, 2015 at 19:31
  • You can't actually achieve a transfer orbit with a period 1/3 that of the final circular orbit, because even lowering your periapsis down to Kerbin's core would still only reduce the semi-major axis of the orbit by half, yielding an orbital period sqrt(1/2^3) ≈ 0.35 > 1/3 times that of the circular target orbit. A factor of 2/3 or 3/4 (for a four-satellite constellation) is quite doable, though.
    – Ilmari Karonen
    Commented Dec 18, 2018 at 4:31
  • Also, it's probably worth noting that having KER installed makes all this a lot easier, since it directly shows you your current orbital period. Otherwise you'll have to do the math for the transfer orbits yourself (remembering to correct for the fact that KSP measures altitude from sea level, not from Kerbin's center), and especially fine-tuning the final orbits to have matching periods so that they won't drift out of alignment can be quite tedious.
    – Ilmari Karonen
    Commented Dec 18, 2018 at 4:40
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Another approach would be to give them a little bit extra fuel for maneuvers and get them as close as you can to being evenly spaced, then decide one of them to use as the baseline, and move the other two in relation to that one. Set the base satellite as your target, then play around with planning small retrograde or prograde burns until you get the correct distance at closest approach. The correct distance should be (orbital height + radius of Kerbin)*sqrt(3). Formula gotten from here, radius of circumscribed circle, solved for side length (a).

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I have created an Excel Workbook that will calculate this precisely for you. You can find it here: Satellite Spacing Calculator

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