RTS GET LOADED OBJECT
That command will return the 3D Object number for a component of the "Real-Time Sky System" object.
Objects ID are these one :

0 = Sky (Background sky color)
1 = Clouds
2 = Stars
3 = Sun
4 = Moon
5 = Light halo around the sun
6 = Ground
7 = Default sky-fog object
8 = Light illumination on the horizon when sun wake up and down.
9 = Background (Mountains, Cities, ...)
SYNTAX
ObjectNumber = RTS Get Loaded Object( IDObjet )
ADDITIONAL INFORMATIONS
RTSKYSYSTEM Commands Menu
Index
SAMPLE
Demonstration Sample