Adding new selection parameters for Tycho stars

[Altas]

(I'll just assume this goes in this forum.)

I would like to add new selection parameters for stars (the thing where stars can be selected by typing in a phrase, accessed by the enter key). Editing my starnames.dat file to add new phrases for hipparcos catalogue stars has not been an issue, but there are specific Tycho stars I want that lack a hipparcos catalogue entry, thus I am stumped. Please let me know if this is possible and what is involved to do this.

[selden]

The [return] name [return] selection displays in its "tab completion list" the names of objects which start with the letters that have been typed so far. Typing Tabs will cause Celestia to step through those names.

For Celestia to display names of stars in that list, those Stars have to be defined in STC catalog files which give them the names you want to see. The names must be provided as quoted strings.

For example,

Code: Select all

Star  "Tycho_123-456" {
RA 1.0
Dec 1.0
Distance 1.0
StellarType "G5"
}


will cause the name Tycho_123-456 to appear in the "tab completion list".

Starting with Celestia v1.4.0, Star definitions in STC catalogs no longer require HIP numbers to be associated with them.

[ajtribick]

If you want to add a name for a Tycho star in starnames.dat, you have to use the internal number for that star. The internal number for Hipparcos stars is the same as the HIP number, but for TYC the rules are slightly more complicated.

TYC aaaa-bbbbb-c becomes cbbbbbaaaa

E.g. TYC 197-37-1 becomes 1000370197.

So to call TYC 197-37-1 "Foo" using starnames.dat you would add the line:

1000370197:Foo

to starnames.dat. To define the star TYC 197-37-1 and name it "Foo" using a .stc file you would use the following code:

Code: Select all

1000370197 "Foo"
{
   RA 125.7083
   Dec 1.8594
   Distance 149
   SpectralType "G1V"
   AppMag 8.70
}

To just define the star without creating a name for it, remove "Foo" from the code.

[Altas]

Thank you for your responses. Chaos syndrome, the first half of your explanation is precisely what I was looking for.

[StarSeeker]

Small world.