Outer space, also known as just “space,” is the vast expanse beyond Earth’s atmosphere. It is home to stars, planets, galaxies, and a variety of other celestial bodies, each with their own unique properties and behaviors. Humans have been studying and exploring space for centuries, from early observations of the stars and planets to modern-day missions to study distant objects using telescopes, spacecraft, and other tools. Some of the most exciting discoveries in space include the existence of black holes, the origins of the universe, and the possibility of finding habitable planets beyond our own solar system.