Thousands of years ago, humans believed that Earth was the center of the universe, that the world they lived on was all there was. Truthfully, the solar system extends almost halfway to the nearest star. And it is composed of not only planets, asteroids, and comets, but also powerful forces and vast fields of energy. This is our solar system's big backyard. The cold, dark world that lies at the farthest reaches of our solar...
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Teen & Young Adult