Planetary Orbit Help??

[Mondas]

I an am newbie and this is my first post. I am trying to create an extra planet for the sol system. I got the planet set up ok. But I want to change the orbit so it comes into the system orbits the sun but instead as it passes the sun it will go through the astroid belt and back out into space. Its the planet Nibiru with a 3600 year orbit . I don't know how to upload an image so here is a link to the image. Any help would be hot.

http://www.sitchin.com/imagesB/nibiru2.jpg

[Hungry4info]

What you should do is change the eccentricity. The eccentricity is how un-circular the orbit is. 0 is perfect circle, 0.9999... is very elongated. It must be from 0, and less than 1, or in interval notation, [0,1).

I would suggest changing the eccentricity, and playing with it until it is how you want it.

[Mondas]

I will give that a try and see if that works

[selden]

Apparently Damon Elkins has already created an SSC for the hypothetical planet Nabiru which matches its supposed orbital parameters quite well. You might want to contact him to get a copy.

http://www.damonelkins.com/blog/?p=6#comments

[Mondas]

The eccentricity didn't help. it changed it from an eliptic to circular orbit.

[selden]

Mondas,

Exactly what is in your SSC file?

Eccentricity 0
is a circle.
Typing something Celestia doesn't recognize might also cause it to draw a circle.

You need to specify something like

Code: Select all

"Nibiru" "Sol"
{
Radius 8500
Texture "Nibiru.*"

EllipticalOrbit
  {
   Period 3600
   SemiMajorAxis 240
   Eccentricity 0.999
   Inclination -150
   AscendingNode 200
   ArgOfPericenter 300
   MeanAnomaly 0
   Epoch "2012 12 21"
  }
}


I'll leave it to you to set the parameters to more appropriate values.

[Mondas]

Thanks a bunch. Damon got it working. I am just trying to figure out how to change the position of the planet to get it closer to the sun. Do you know how to do that?

[Mondas]

I am still trying to figure out how to change the position of the planet to get it closer to the sun with no luck yet. But I have another question? I like clicking the option to show the planetary orbits but when I did that Ploto's orbit isn't highlighted. I can't seem to figure that one out either. Anyone know about these two things?

[Damon]

Mondas, if you select Pluto as the object through the "navigation" tab, then select "goto", it will highlight Pluto's orbit.

To bring Nibiru close to the Sun, you can fast forward in time by clicking the "L" key several times. Then, as Nibiru passes halfway to the Sun, it will speed up, so you'll want to click the "K" key to slow it down as it reaches the asteroid belt and around perihelion.

Hope this helps.

Damon

[Mondas]

I don't think I explained it clear enough. When I start the program I can see a blue line for the orbits of each planet mercury out to neptune. Even Nibiru that was added has this blue line. but it bypasses pluto. Pluto's blue line doesn't even show up. As Far as changing the position. I didn't mean to speed it up. I want to follow current theories and place it closer to the system in real time. Supposedly next year it will enter the system but it can't as far out as it is. I want to move it closer without speeding the program up.

[Damon]

I still have blue orbit rings for all planets including Pluto. Someone else might help you more on that.

As for Nibiru...
You can change the position by changing the Mean Anomaly to 359.2 to bring Nibiru just short of the asteroid belt "under" the ecliptic on its inbound portion of orbit.
IMHO, current theories which place Nibiru that close are wrong for the simple reason that it would now be readily observable.

[Mondas]

Thanks.. I will try the mean... As for the theory... I don't think its that close either. But its fun to play around with it.

[Hungry4info]

In the default version of Celestia, Pluto doesn't... and shouldn't have a blue line. Blue lines are for planets. Pluto is not a planet.

[Damon]

I'm still using Celestia version 1.4.1 which has default with Pluto still a planet.
It was downgraded latter part of 2006 after the time of that version.
Wasn't aware that it'd been changed in later version(s).
Thanks for update.

[selden]

Hungry,

Celestia v1.5.0 doesn't show an orbital path for Pluto (actually for the Pluto-Charon Barycenter) because of a defect in Celestia, not because Pluto is no longer a planet. Celestia does not yet draw the orbits of the new ReferencePoint objects.

Celestia has not yet caught up with the IAU's planetary specifications. For example, if you type a 9, which selects the 9th planet of the currently selected Star, the Pluto-Charon barycenter will be selected.

It is to be hoped that a future version of Celestia (perhaps even v1.5.1) will allow selection of dwarf planets, and the drawing of orbit paths for ReferencePoints.