They're doing a lot of stuff with sampling air and so forth, inside the spacecraft and trying to move things around. That silly "planet Earth" plush, dubbed the "zero G indicator" by SpaceX, is in the way, and while trying to do something one of the astronauts bumps it aside.
It ricochets around the capsule and ends up right back in his face, which is the kind of detail no fictional space movie has ever done.
Heh.