Source: Starfinder Core Rulebook p.106
As a move action, you can create a minor shield of compressed gravity waves, granting you a +1 circumstance bonus to your AC. The shield lasts for 1 round or until you leave graviton mode.
When you are attuned or fully attuned, as a move action, you can create a disk of massive gravitational energies that is capable of deflecting incoming attacks. Choose one edge of your space. The shield extends along three continuous edges in a straight line centered on the chosen edge. The shield provides cover against attacks coming from its far side, but not against attacks originating from the side you're on. If you move, you can reposition your shield as part of your move action, moving it to a different edge of your space. You must use one of your hands to direct and maintain an active gravity shield. You cannot use this version of the gravity shield at the same time you use this revelation to gain a circumstance bonus to your AC. This gravity shield also lasts 1 round or until you leave graviton mode.