the solar family - part 15 of 18. makes an introductory study of the planets - their evolution, motions, sizes, and satellites. describes the evolution of the solar system according to planetesimal hypothesis, and traces the real and apparent motions of t - 穀神星 矮行星 個影片檔及 b 捲影像00:35太陽系, 外太空
the solar family - part 14 of 18. makes an introductory study of the planets - their evolution, motions, sizes, and satellites. describes the evolution of the solar system according to planetesimal hypothesis, and traces the real and apparent motions of t - 穀神星 矮行星 個影片檔及 b 捲影像00:36小行星, 地球, 木星