This book is not a science book, but there is a little bit of science in the aliens’ travels. The aliens and their mama live on Mercury, the smallest planet, which is closest to the sun. When the aliens leave home, they pass all the other planets in our solar system, in order of the planets’ distance from the sun. They start by zipping past Venus, which is the brightest planet in our night sky. Next they pass Earth, our home, the watery blue planet; and after that comes Mars, the red planet. Then the two alien brothers fly by the fifth planet from the sun, Jupiter, which is made of gases, and come to Saturn, with its glorious rings. The last little alien passes Uranus, whose atmosphere is icy, and finally settles on Neptune (where winds blow as fast as 1,290 miles per hour!), the farthest planet from the sun.
Mark Fearing researched the planets so that he could depict them as accurately as possible, and based their coloration on photographs provided by NASA. All eight planets are shown on the endpapers, though the distance between them is not to scale. For more information about our solar system, visit www.nasa.gov.