In this descriptive nonfiction text, the author includes sensory details to create mental pictures for readers as they tour 40 degrees north and south latitudes. During the same week in January, readers feel the cold of winter in the Northern Hemisphere and the warmth of summer in the Southern Hemisphere. Readers learn how the seasons are determined not just on the time of year, but also on location on Earth as it tilts in space. Maps, illustrations, and photographs support the text.