Kuiper Belt & Solar System Barycenter

[FarGetaNik]

Hi Everyone,
I?m working on an add-on which includes the most important transneptunian objects by now, but since there are enough on the motherlode, I?ll provide much more features. Still not sure if I?ll upload it... well my question:

Wouldn?t it be more precise if KBOs orbit the Solar System Barycenter?
It seems that all default-TNOs of Celestia orbit the Sun, but it?s wobbling around because of the heavy gas giants. For Pluto?s moons: They orbit the system?s barycenter, not Pluto. For KBOs, the "wobbling" is about 1 million km (Not very much, ok...). If you follow SSB and zoom to a TNO, you?ll recognice the movement of it?s Orbit.

By the way, a major feature of my addon will be a reference point (KBOs). All objects added will appear in the solar system browser in this reference point, so they won?t clutter the solar system browser. Still, all objects should orbit the sun, so I added for every object the lines:

Code: Select all

    OrbitFrame   { EclipticJ2000 { Center "Sol" } }
    BodyFrame   { EclipticJ2000 { Center "Sol" } }

That?s why I?m asking, maybe the center should be Solar System Barycenter...

[John Van Vliet]

using a spice orbit works
have a look at my pluto-charon
http://forum.celestialmatters.org/viewt ... f=18&t=599
-- the ssc file
https://drive.google.com/file/d/0B6ZYAd ... sp=sharing

For most things the spice kernels have ssb and the sun origins

there is a spice section over at celestial matters
http://forum.celestialmatters.org/viewf ... ffcaba9a9c

I also place comets in the KBO group
http://forum.celestialmatters.org/viewt ... f=18&t=578

[FarGetaNik]

Hm not really what I asked for, I never dealt with spice. Anyway, the idea is good, but where do I get the orbital data from? Using the Small Data Base seems more reasonable for those objects with more or less uncertain orbital elements.
By now I think the SSB would be a more accurate barycenter.
I wonder why the default KBOs orbit the Sun. And, where is the data for CostomOrbit hidden in Celestia?