Asimov, Isaac

Describes the characteristics and value of tropical rain forests, why they are disappearing, and how to save them.

Explains why stars in the night sky appear to twinkle.

A step-by-step description of how an eclipse occurs and the differences between a lunar and a solar eclipse.

Discusses the origins, physical makeup, and relationship to earth of the huge star called the sun.

Briefly describes the characteristics of the sun, planets, and stars of our solar system and some of the still unsolved mysteries of the universe.

Discusses how litter damages the environment and how to dispose of it properly.

Discusses the causes and damaging effects of oil spills and ways to protect the land and sea from oil pollution.

Explores the possibility of establishing colonies in space, traveling by starship to other galaxies, and meeting extraterrestrials.

Discusses the formation and peculiar features of the universe, particularly stars and galaxies emitting special types of radio waves.

Discusses the characteristics of comets and meteors and cites both famous appearances and unexplained mysteries connected with them.