Question: Retrograde motion: Consider a distant comet in the "Kuiper belt" (d=40AU from the sun, where 1 AU = 1.5E8 km).
(a) What is the velocity of the comet in its orbit?
(b) If the earth were stationary, how fast in angular velocity (say in units of arcsec/day) would the comet be moving at opposition?
(c) If the comet were stationary in space, how fast in angular velocity would it appear to be moving due to the earth's motion? Would this be in the same direction as your answer in (c), or opposite?
(d) What is the net motion of the comet? In which direction? Which effect dominates - the comet's orbital motion, or the earth's orbital motion?