This film is one of a three part series on celestial bodies, including planets, comets, asteroids, and meteors. This episode focuses on comets and asteroids. Comets, with their characteristic elongated vapor tails have fascinated star gazers throughout time. Asteroids, which are small, minor planets, have been discovered mainly through high powered photography. The film uses 3-D animation, computer-generated images, and deep space photography to reveal some the secret lives of asteroids and comets. The dramatic story of their previous collisions with the earth is presented, along with NASA's plans for protecting the earth from future impacts. ~ Rose of Sharon Winter, All Movie Guide