The Holden crew fly to a certain set of coordinates. At these coordinates they find an asteroid. Asteroids however are not fixed points in space but are circling the sun, just like planets do. The crew would likely have found only empty space at a fixed set of coordinates.
During the shootout a thug manages to activate a grenade, then Miller hits his hand so he drops it on the floor before he could throw it The grenade should go off but it doesn't.
While Alex watches the drone camera display, his monitor is labeled "DRONE...HUD." Drones don't have heads and therefore don't require a Head Up Display (HUD). A HUD is a translucent video display meant for a person to keep their eyes focused on an object while seeing the video display--not something a drone needs.