Introducing Earth -- Naming the planet -- First sightings -- Observing Earth -- Earth in our solar system -- Comparing Earth -- Earth today -- Planet watchers -- Young scientists at work -- What have you learned?
Summary
The third planet from the Sun, Earth is the only planet known to support life. Nicknamed the "Blue Planet," Earth has a unique mix of air, water, and land unlike anything else scientists have seen on other planets. Readers learn this and more!