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Alula Australis missing

Posted: 28.04.2003, 00:04
by granthutchison
Alula Australis (Xi UMa, Hip 55203, HD 98231) seems to be is missing from stars.dat, although its name is listed in starnames.dat.
This has just created a short burst of hair-tearing for me, since I wanted to reproduce the orbit of Alula Australis B (and then some of the other members of the system). So first I added the star as an stc file:

Code: Select all

#Alula Australis
500000 {
   RA 169.54558
   Dec 31.70333
   Distance 27.3
   SpectralType "G0V"
   AppMag 4.33
}

Fine, now there's a star in Celestia. Then I made an ssc for Alula Australis B - but it doesn't appear in Celestia. Check for typos - nothing. So I eventually rename my Alula Australis to just plain "Testing", and up comes its companion.
So if a star is missing from stars.dat, but is still named in starnames.dat, it seems that the non-existent star will "steal" any planets you try to define for a replacement star with the same name. Celestia presumably scans starnames.dat and ties your new planet to the Hip number of the first occurrence of a matching star name - in this case, one that doesn't exist in stars.dat.

Grant

Posted: 28.04.2003, 02:47
by selden
Grant,

Using its real HIP number works just fine, though.
Just replace 500000 by 55203.

Posted: 28.04.2003, 07:59
by granthutchison
selden wrote:Using its real HIP number works just fine, though.
Just replace 500000 by 55203.
Ah, makes sense. Thanks.
So the thing to do with this sort of missing star is to open starnames.dat and search for its name, so that you can find and use the appropriate catalogue number in your stc.

Grant

Posted: 28.04.2003, 12:05
by selden
that's what I did.
Unfortunately, if there's one missing, that suggests there are likely to be others :(