Examples of L dwarf stars

General physics and astronomy discussions not directly related to Celestia
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danielj
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Examples of L dwarf stars

Post #1by danielj » 31.10.2005, 22:22

I downloaded the ldwarf.jpg texture,but it appears that there is no L star in Celestia 1.4.0 FT 1.1 catalogue.I try to write several names of the catalogue of the 400 or so L dwarfs and Celestia accept none.
Can someone give me an example of a L star in Celestia FT 1.1?Or at least a catalogue where I can find them...
Actually I can??t find a L dwarf star in Celestia 1.4.0 pre 6 either.
I know that there is some L dwarfs orbiting the stars.But which are they?The stars with the biggest mass?And what is the threshold for this mass?

ajtribick
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Post #2by ajtribick » 31.10.2005, 22:41

Alula Australis Bb is the only L dwarf in the catalogues supplied with the 1.4.0 preversions, not sure if its in the FT versions though - haven't got round to downloading FT yet.

Judas Maccabeus
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Post #3by Judas Maccabeus » 01.11.2005, 04:43

Aula Australis Bb is in FT 1.1, I just checked. That's the only one I found, though.

(Wish there was a way to display stars of one spectral class in the Star Browser. I could think of several uses for that...)

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danielj
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Post #4by danielj » 01.11.2005, 11:30

And concerning this,what??s the difference between a brown dwarf primary(L dwarf star) and a brown dwarf satellite of a star?Note that you can use the ldwarf.jpg both in the star catalogue or in the extrasolar.ssc.
How can I assign the ldwarf.jpg to the class L star?I put the ldwarf.jpg in the med res in Celestia 1.4.0 pre FT 1.1 and didn??t change the appearance.But in case of Celestia 1.4.0 pre 6,it did.Is it a bug?


Judas Maccabeus wrote:Aula Australis Bb is in FT 1.1, I just checked. That's the only one I found, though.

(Wish there was a way to display stars of one spectral class in the Star Browser. I could think of several uses for that...)

ajtribick
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Post #5by ajtribick » 01.11.2005, 19:52

Alula Australis Bb is defined in "nearstars.stc" in the data folder... .stc files now support a Texture declaration, so all you need to do is add one to the file.

This should work:

Code: Select all

"Alula Australis Bb:XI UMa Bb:53 UMa Bb:Gliese 423 Bb"
{
   OrbitBarycenter "Alula Australis B"
   SpectralType "L"  # brown dwarf
   AbsMag 21         # for approximate radius in Celestia

   Texture "ldwarf.jpg"

   EllipticalOrbit {
      Period          0.0109 # 3.981dy
      SemiMajorAxis   0.056  # mass ratio 1.05:0.08
      Eccentricity    0
   }
}


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