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Author Topic: Inclination VS the Obliquity or the Orbital Parent  (Read 4827 times)

tkulogo

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Inclination VS the Obliquity or the Orbital Parent
« on: August 31, 2017, 11:58:28 AM »
Is there an obvious way to align a satellite’s orbital inclination with the obliquity (axial tilt) of the orbital parent (like the moons of Uranus)? I’d be happy with just knowing what to enter in the inclination and right ascension, though a way to just set it to start that way would be better.

SyzygyΣE

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Re: Inclination VS the Obliquity or the Orbital Parent
« Reply #1 on: August 31, 2017, 02:51:44 PM »
Yeah. There is a way. Here is the procedure.
  • Place a planet and pause the simulation.
  • Add > Rings > Moon Swarm > Ring Settings
  • In settings, change ring configuration from "Torus" to "Ring" and change the number of bodies to 1.
  • Spawn the ring. The moon will come out massive so just select it and make its mass 1 kg. We're only putting it there for comparison purposes.
  • Resume the simulation so that the orbit of the moon is registered but quickly pause it again.
  • Look into the moon's properties. Motion tab > Inclination and Right Ascension.
  • Note down these two values and delete the moon.
  • Now, putting these values to any new moon you add will align their orbits to a planet's axis.
You might think that we can just spawn a bunch of moons using Moon Swarm and have all their orbits aligned, but these are Earth's moon, not random moons, so you'll end up with them all looking the same if you do this. Therefore, we only spawn one moon in this way—it automatically aligns to the planet's axis—to check its orbital properties and apply them to more random moons.

I feel this procedure is a little more complex than it really needs to be. Would be nice if there was a button called "Align Moon To Axis" or something that does this in one click.
« Last Edit: August 31, 2017, 06:38:34 PM by SyzygyΣE »

tkulogo

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Re: Inclination VS the Obliquity or the Orbital Parent
« Reply #2 on: September 01, 2017, 05:12:14 AM »
Thank you, that will work just fine for now. I suspect in the future there will be a way to set a bodies reference north to the north pole of the orbital parent, but they have debug the orbital parent code first.

Jar

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Re: Inclination VS the Obliquity or the Orbital Parent
« Reply #3 on: September 01, 2017, 09:47:40 AM »
As SyzygyΣE said, there is a way, but no, there is no obvious way.  :)

Here's what I said to SyzygyΣE in response to his suggestion on the Steam forum for an easier way to do this:

This is a good idea that's been suggested a handful of times before.

It is on our to-do list currently, though I imagined it as being able to add the moon (or any other body) on its parent's orbital plane. But simply being able to set it after it's already added, like the Auto Orbit button, might be a more simple solution. I'll suggest this. Thanks!