The five planets referred to are Mars, Jupiter, Saturn, Venus, and Mercury. The twenty-eight constellations are the stars which occupy fixed positions in the sky while the five planets, the sun, and the moon rotate. They represent the gods that regulate heaven and the four seasons. Since this handscroll only shows the five planets and twelve constellations, it appears that the complete work consisted of two volumes and that the second volume with the rest of the constellations has been lost.