Did you know that as high-speed Mercury zooms through space it travels 31 miles (50 km) every second, or that a year on Mercury lasts just 88 days? And did you know that if Earth were the size of a baseball, little Mercury would be no bigger than a ping-pong ball? These and dozens of other fascinating facts provide a perfect high-interest introduction to the planet that's closest to the Sun, Mercury. Filled with information perfectly suited to a second-grade audience, this accessible, high-impact book combines solid science, technology, and even math with up-to-the-minute information, odd and often quirky facts, and astounding space photography. It also provides plenty of surprises and teachable moments that will draw young children into a rewarding, kid-friendly reading experience.