Rings around stars

[ANDREA]

After publishing in Celestia Motherlode Creators my "TheOrrery-English .cel" file with all the needed stuff included, that you can find at

http://www.celestiamotherlode.net/creators/andrea/The-Orrery-English.zip

whose you can know something here

http://www.shatters.net/forum/viewtopic.php?p=42694#42694

now I would like to put something between Mars and Jupiter orbits, that could remember the Minor Planets Main Belt, and adding there only one asteroid (probably Ida with Dactyl), in order to show it.
My problem is that up to now, if I don't mistake, I have never seen rings around stars, so I don't know if this can be done or not and, if the answer is yes, how to do it.
Someone can give me information on the matter, please?
Thanks a lot.
By

Andrea

[selden]

One way to do it is to create a fake planet that's inside the sun and put rings around that planet.

[ANDREA]

One way to do it is to create a fake planet that's inside the sun and put rings around that planet.

Selden, do you mean something like this?

Code: Select all

"MPBelt" "Del Pav"
{
   Texture "neptune2.jpg"
      Radius 1000
      EllipticalOrbit
   {
         Period        0.001  # yr
        SemiMajorAxis  0.001 # au
         Eccentricity 0.01

   Rings {
      Inner   33000000
      Outer   36000000
      Texture "MPBelt.jpg"
      Color  [ 1.0 0.98 0.98 ]
   }
}

I think that the Inner-Outer values are wrong, because I don't see the ring.
And, if I remember correctly, the rings distance from a planet is in Km, while the planets distance from the star is in AU.
So I converted the 0.22-0.24 width of the ring (because halfway between Mars and Jupiter, that have

Code: Select all

Mars" "Del Pav"
   SemiMajorAxis     0.2000

"Jupiter" "Del Pav"
   SemiMajorAxis     0.2500

multiplying by 150,000,000 Km, and applied the 33 and 36 million Km distance for the ring, but it doesn't work.
Moreover, MPBelt doen't appear as planet in the Solar System Browser.
Where am I making mistakes?
Thanks a lot for your kindness, Selden.

Andrea

[selden]

Andrea,

I'm sorry to say that, as best I can tell, Celestia will not draw rings if you are "too far" from the central body In otherwords, sometimes the rings are visible and sometimes they are not, depending on how distant you are from the sun.

However, you might want to consider using one of my "graticule" models with a different picture -- one that looks like rings of asteroids instead of a gridwork.


See http://www.lepp.cornell.edu/~seb/celestia/graticules.html#2

[ANDREA]

Andrea,
However, you might want to consider using one of my "graticule" models with a different picture -- one that looks like rings of asteroids instead of a gridwork.See http://www.lepp.cornell.edu/~seb/celestia/graticules.html#2

Selden, you always have a solution!
Thank you, I'll give a look and try.
By

Andrea

[ANDREA]

Selden, you always have a solution! Thank you, I'll give a look and try. By Andrea

OK Selden, downloaded, opened, and tried to understand something.
Here are my results:
I'm using the EclipticAU.dsc only, that I have modified as follows:

Code: Select all

Nebula " " {
   Mesh "graticule.cmod"
   Axis [ 1 0 0 ] Angle 90
   Position [ 0.00326167  0.0 0.0 ]
   Radius 0.00060000
}

As you see in the following image, this is what I would need, i.e. a single circle (but much thicker than this) in the given position.



How can I modify a .cmod file?
What software do I need, the same for 3ds files?
Thank you for your help

Andrea

[selden]

Andrea,

The cmod graticule draws one-pixel-wide lines in space. It uses the OpenGL "line" primitive. The current CMOD primitives do not provide any way to change the width of the line, only its color and opacity. Sorry.

It probably would be easier to use graticules-v2.zip
That kind of graticule uses a flat 3DS model. You can provide your own picture for its surface texture image.

[ANDREA]

Andrea, The cmod graticule draws one-pixel-wide lines in space. It uses the OpenGL "line" primitive. The current CMOD primitives do not provide any way to change the width of the line, only its color and opacity. Sorry.
It probably would be easier to use graticules-v2.zip
That kind of graticule uses a flat 3DS model. You can provide your own picture for its surface texture image.

Thank you Selden, I'll try this new way.
By soon

Andrea