You just need to download the Forgetools to gain access to the default Planet/ STAR entity files. Copy and paste these files into a new folder, then place this into your Mods folder for either Vanilla Sins or Entrenchment. Using notepad to open the Planet or Star entities, press ctrl F and type moveAreaRadius (or go right to the bottom of the Planet entitiy file) which will have the parameter hyperspaceExitRadius  below it. These two parameters determine the gravity size and the area at which you will be able to jump to hyperspace.

Zrazor got it!!    also look at the older X10 mod on wincustomize if you have 1.05 Vanilla or just want to check out the files. Very very cool!!  I was hoping he would update it for Entrenchment, but havent seen him online for awhile. Shame, its a dynamite mod!! 

-Teal