A spacecraft approaching the planet Saturn reaches point A with a velocity vA of magnitude 21 km/s.

Question:

A spacecraft approaching the planet Saturn reaches point A with a velocity vA of magnitude 21 km/s. It is placed in an elliptic orbit about Saturn so that it will be able to periodically examine Tethys, one of Saturn??s moons. Tethys is in a circular orbit of radius 295 × 103 km about the center of Saturn, traveling at a speed of 11.3 km/s. Determine

(a) The decrease in speed required by the spacecraft at A to achieve the desired orbit,

(b) The speed of the spacecraft when it reaches the orbit of Tethys at B.