\f(a) In the reference frame with the origin at the astronaut, you might have decided to have (i) the astronaut rotating with respect to the frame or (ii) not. If you drew the reference frame then, from the perspective of a person on the space station, in case (i) the reference frame would be translating in time but not rotating. If you drew the reference frame you chose with origin at the space station, what would it look like from the perspective of the astronaut? Some terms you might want to use are rotate, revolve, translate, and spiral