When separated from a gravity plane and in open space, you have learned to master the skills that space faring creatures use to control their body in open space when not affected by another gravity plane. It allows you to attack a combatant at advantage who does not have this skill when in open space. 

This feat also helps when a ships gravity plane shifts. This can cause objects to fly in all different directions unless they are tied down, even up. While others without Zero Gravity Combat are making dex checks to avoid damage, you are able to make a check with advantage to avoid any negative affects at all.

Can use missile weapons or thrown items to change direction if out of a gravity plane to get back into a gravity plane if within 100 feet.