Perfect for Earth Day! Climb aboard a giant spaceship . . . the Earth! In glorious art, G. Brian Karas illuminates our Earth and its cycles and does a brilliant job of making the concepts of rotation and revolution understandable. As you travel, watch shadows disappear into night, and feel the sun on your face as winter turns into spring. All these amazing things happen because the Earth is constantly in motion, spinning and circling, gliding and tilting. As passengers of the Earth, our voyage never ends!