Orbit Radius of Moons

[Trolls]

I'm new to this program and I'm having a bit of trouble setting the correct orbit radius for the moons orbiting my custom planet. I was under the impression the SemiMajorAxis value is what needs to be changed, but despite having different values for each moon, they are all appearing in the same orbit path.
On a related note, how does the value given relate to actual distances in km? For example, if I wanted a moon to have an orbit radius of 300000km, what would I type?

[selden]

You'll have to provide the text of exactly what you're using in order for anyone to be able to suggest a fix.

You might start by using the SSC orbits of existing moons. See the file Celestia/data/solarsys.ssc for some of them.

The SemiMajorAxis value is in km.

Celestia's "console log" may include an error message. Type a tilde to see it.

[t00fri]

I'm new to this program and I'm having a bit of trouble setting the correct orbit radius for the moons orbiting my custom planet. I was under the impression the SemiMajorAxis value is what needs to be changed, but despite having different values for each moon, they are all appearing in the same orbit path.
On a related note, how does the value given relate to actual distances in km? For example, if I wanted a moon to have an orbit radius of 300000km, what would I type?

To stay with your example: have a look at data/solarsys.ssc under "Moon" "Sol/Earth". You sure know the Earth-Moon distance by heart. So have a look at the entry: "SemiMajorAxis".

That should fix the dimensions for you

Bye Fridger

[Trolls]

I copied the text from Earth's moon and altered the radius and semimajoraxis values, nothing more. The radius changes seem to be working. Here is the code I've used for a couple of the moons:

Code: Select all

"Aryth" "Ebersun/Eberron"
{
   Texture "moon.*"
   BumpMap "moonbump.*"
   BumpHeight 0.3
   Radius   800
   # Oblateness 0.002

   CustomOrbit "moon"
   EllipticalOrbit {
      Period           27.321661
      SemiMajorAxis    353600
      Eccentricity     0.054900
      Inclination      5.15
   }

   Obliquity      23.45 # mean axis
   EquatorAscendingNode    0.0  # mean axis
   RotationOffset       38

   Albedo           0.12
}

"Vult" "Ebersun/Eberron"
{
   Texture "moon.*"
   BumpMap "moonbump.*"
   BumpHeight 0.3
   Radius   1440
   # Oblateness 0.002

   CustomOrbit "moon"
   EllipticalOrbit {
      Period           27.321661
      SemiMajorAxis    403200
      Eccentricity     0.054900
      Inclination      5.15
   }

   Obliquity      23.45 # mean axis
   EquatorAscendingNode    0.0  # mean axis
   RotationOffset       38

   Albedo           0.12
}


[t00fri]

If you could educate me what "Aryth" "Ebersun/Eberron" and "Vult" "Ebersun/Eberron" are and where I can see them with my biiiiiiiiiiiiiiiiiiiiiig telescope, I would be grateful.

Bye Fridger

[selden]

"CustomOrbit"s are defined internally in Celestia for specific solar system bodies. They override whatever EllipticalOrbit accompanies them.

Delete the CustomOrbit specifications.

[Trolls]

"CustomOrbit"s are defined internally in Celestia for specific solar system bodies. They override whatever EllipticalOrbit accompanies them.

Delete the CustomOrbit specifications.

Ah ha! Problem solved, thanks

[Evil Dr Ganymede]

If you could educate me what "Aryth" "Ebersun/Eberron" and "Vult" "Ebersun/Eberron" are and where I can see them with my biiiiiiiiiiiiiiiiiiiiiig telescope, I would be grateful.

Bye Fridger

They're fictional. Eberron is a tabletop roleplaying game (based on D&D), these are the moons and its sun.