Comet Machholz

[Nerull]

Comet Machholz is just becomming a naked eye object, so here are the orbital elements, paste this into data\comets.ssc

Code: Select all

"Machholz" "Sol"
{
   Class "comet"
   Texture "astroid.jpg"
   Mesh "roughsphere.cms"
   
   EllipticalOrbit
   {
      Epoch 2453400.5
      Period 119037.5908125275558340091289128
      PericenterDistance 1.205088
      Eccentricity 0.999502
      Inclination 38.5891
      AscendingNode 93.6269
      ArgOfPericenter 19.5023
      MeanAnomaly 0
   }
   Radius 7.5
   RotationPeriod 170
   
   Albedo 0.04
}


This is my first conversion to celestia format, so it may not be completely correct, however a quick check shows the comet in the right position in the sky, so I think it is.


Increasing your orbit line segments is recommended, this one goes far, and the orbit looks very blocky near earth with the default 100.

[Bob Hegwood]

You MAY wish to change "astroid.jpg" to the name of a texture
which COMES with Celestia. Try "asteroid.jpg"

Take care, Bob

[Nerull]

Oops

Yes, do that, I flew to it, but I didn't think anything of it being white...it is a comet, afterall

[Adirondack]

Nerull,

if I had known that you already did make this job, I would have not spent my time to make a ssc-file by myself.

BTW: Your code seems to be correct, but the period is probably 119039.84 yrs. (AFAIK)

To whom it concerns: You find my ssc-file at the Celestia Motherlode
within the comets section -> http://www.celestiamotherlode.net/catalog/comets.php


What is the source of the following values, you use in your code:

Radius
RotationPeriod
Albedo

Are they just a guess? Or can you point me to a verified source?

Adirondack

[Nerull]

I took them from the other comets in comets.ssc

[Adirondack]

Ahh, but I guess "Machholz" is not so big and it doesn't rotate as fast as your code describes. Unfortunately I did not found any information about these parameters at MPC or elsewhere.

I tried your code, but your Machholz is too far west. It should be rendered in Celestia on January, 7th 2005 near the Pleiades.

Try my .ssc-file (see above) and compare the position of the comet with yours.

Adirondack