I know I might get a lot of hate for this, but I just want to float in space like I do in my ships...! I love floating in zero G...
The only way to do it while jetpacking in space is to hold down a directional button and while moving press J to deactivate jetpack. You will then float endlessly in the last direction you were traveling until you either re-activate the jetpack or you come near gravity. Unfortunately you have to put up with the screen shaking constantly while floating with the jetpack deactivated. Jetpack mechanics, especially while in space, need a LOT of work..... I keep hoping that one day we get a real jetpack (like Space Engineers jetpack mechanics). What we currently have in-game leaves a LOT to be desired.
The problem then is that while moving with the jetpack off, the player runs in the direction he's drifting (the "screen shaking" krazzy described) which is utterly ridiculous.