The Milky Way is just one of billions of galaxies in the universe. Yet by exploring the galaxy we call home, we have been able to uncover some of the universe's many unknowns. This illuminating volume carefully breaks down the features of the Milky Way galaxy. It explains such characteristics as size, shape, and age; examines planets, stars, and star clusters; and delves into such concepts as black holes and dark matter. Important terms are explained,...

Readers discover the difference between natural and human-made satellites in this entertaining volume. The narrative reveals fun facts about various moons in the Earth's solar system, such as Earth's moon and how it might have been formed, the moons of Mars, Jupiter, Saturn, Uranus, and Neptune, and those of the dwarf planet Pluto. It also explains the terms "orbit," "spin," "rotation," and "eclipse." The volume provides "Think About It" boxes to...

When people think of objects in the sky, they may think of planets, the sun, moon, and constellations. Many other bodies orbit Earth and the sun, however. The sky below Earth's atmosphere holds many interesting objects as well. We may not need a telescope to see them, but they are no less awe-inspiring. Readers are introduced to the dazzling phenomena of stars, galaxies, lightning, meteoroids, comets, auroras, rainbows, black holes, and even satellites...

Explains how leaves change their colors in autumn and then separate from the tree as the tree prepares for winter.

A vampire and a monster give a simple introduction to the composition and functions of blood.

Describes the many different ways animals cope with winter, including migration, hibernation, and food storage.

Explains how ants live and work together to build and maintain their cities.

Explains the phases of the moon--the changes that seem to happen to it as it goes around Earth.

Explains how bacteria and viruses affect the human body and how the body fights them.