Parallax refers to Question 9Answer a. a real movement of a nearby star with respect to the background stars due to the change of our vantage point as we orbit the Sun b. change in the position of the moon due to the change of our vantage point as we orbit the sun c. retrograde motion of planets d. an apparent movement of a nearby star with respect to the background stars due to the change of our vantage point as we orbit the sun e. how fast the stars are moving with respect to us in space