Gamma Leporis B Question

[Dollan]

Okay, the Newstars file that adds companions to multiple star systems does not supply the companion for Gamma Leporis. My question is, how do I do this?

Should I just create a new ssc file and add an emissive planet for the B components, then treat the following planets as if they were moons of this component?

Or is there some other way that I cna do this, so that, for the planetary companions, I can make a seperate ssc file?

...John...

[Rassilon]

I would use an ssc def instead of an actual star...The 2 stars will conflict with your solar system and cause planets to disappear...

[granthutchison]

They're ~900AU apart, so they revolve too slowly for anyone to have calculated an orbit that you could put in an ssc. That's also far enough apart that they're not going to tread on each other's solar systems when defined in Celestia, as Rass' fears.
So I'd just set up a new star in a little stc file that looks like this:

Code: Select all

355550 "GAM Lep B:13 Lep B:HD 38392"
{
   RA 86.1105
   Dec -22.42175
   Distance 29.25527
   SpectralType "G5V"
   AppMag 6.4
}

(Use whatever imaginary Hip number suits your other add-ons.)

Grant

[Dollan]

Oh, okay... cool, thanks!

Couple of questions: would it NEED an HIP number? Also, are there any other statistics that could or should go with a star? And finally, I have all of my ArcBuilder add-ons in their own folder under extras (Extras/ArcBuilder Universe/Gamma Leporis B as an example). Could the stc file go the Gamma Leporis B folder, or does it need to go into the Data folder?

(yes, I'm in new territory again... heh)

...John...

They're ~900AU apart, so they revolve too slowly for anyone to have calculated an orbit that you could put in an ssc. That's also far enough apart that they're not going to tread on each other's solar systems when defined in Celestia, as Rass' fears.
So I'd just set up a new star in a little stc file that looks like this:

Code: Select all

355550 "GAM Lep B:13 Lep B:HD 38392"
{
   RA 86.1105
   Dec -22.42175
   Distance 29.25527
   SpectralType "G5V"
   AppMag 6.4
}

(Use whatever imaginary Hip number suits your other add-ons.)

Grant

[granthutchison]

Couple of questions: would it NEED an HIP number?

Yes, Celestia uses the number for internal reference, so stars that don't have Hip or Tyc numbers need to be assigned an imaginary code.

Also, are there any other statistics that could or should go with a star?

Nope, that's the whole definition as far as Celestia's concerned.

Could the stc file go the Gamma Leporis B folder, or does it need to go into the Data folder?

It can go in the Gamma Leporis B folder, along with the ssc for your planetary system. It keeps everything in one directory you can move easily to new Celestia versions.

Grant

[Dollan]

Okay, got the star there (I didn't realize that you had already placed a HIP number there). I'm probably picking at nits, but I am curious: since there is no place to define it in the stc things like rotation, etc., how is that determined? Random?

Of course, now I can't get my planetary system to show up. I named the stc file "Gamma Leporis B", and I did the same thing with the ssc file. Am I buggering up?

...John...

[Dollan]

Oop... I figured it out. I didn't realize that I had to name it "GAM lep B"

...John...

[granthutchison]

... since there is no place to define it in the stc things like rotation, etc., how is that determined? Random?

Not quite. Celestia uses the average temperature and rotation period for a star of the spectral class specified by the stc. Radius is then calculated from temperature and brightness ... Celestia works out how big a black body radiator needs to be in order to be as bright as is specified in the stc.

Of course, now I can't get my planetary system to show up.

Your planets need to be defined as being in orbit around one of the star names specified in the stc ... if you're using something like "Gamma Leporis B" Celestia won't recognize that that's the same object as the "GAM Lep B" I've specified in the stc.

Grant

[Dollan]

Not quite. Celestia uses the average temperature and rotation period for a star of the spectral class specified by the stc. Radius is then calculated from temperature and brightness ... Celestia works out how big a black body radiator needs to be in order to be as bright as is specified in the stc.

Ah, I see. That might be a neat feature to implement in some future version, the ability to determine rotational periods and such yourself. Or, for that amtter, the oblateness of a star (thinking of the classic egg-shaped star such as Altair or Beta Hydri).

Your planets need to be defined as being in orbit around one of the star names specified in the stc ... if you're using something like "Gamma Leporis B" Celestia won't recognize that that's the same object as the "GAM Lep B" I've specified in the stc.

Yeah, I finally figured that out. I changed it to "Gamma Leporis B" for consistency's sake on my part.

I very much appreciate your help!

...John...

Grant[/quote]