.minecraft/config folder, find a mod config with dimension -1005 and change it.
It also seems possible one of the mods is starting at dimension -1000 and working backwards from there, like -1000, -1001, -1002 etc, so look for any config with -1000 also. Like I said already, you should start by looking at "ExtraPlanets" and "GalaxySpace". Probably, these two mods are overlapping. Do you really need both of them?
More generally, you should update your Galacticraft to the latest version 489 - not 465 which you have. 489 is better for you.