What planet is known as Earth's twin? Venus The two planets are about the same size, and Venus also has mountains, canyons, and volcanoes. However, Venus is much hotter than Earth--with temperatures reaching 880 F. It is also unlike Earth because its thick atmosphere is filled with poisonous gases. Early readers will be taken on a journey through outer space as they learn these and other fascinating facts about Venus. Each 24-page book features controlled...