A planetary system consists of a star and all the celestial bodies that are bound to it by gravity, including planets, moons, asteroids, and comets. Our own Solar System is a prime example, featuring the Sun at its center and eight major planets, including Earth, Mars, and Jupiter. Planetary systems can vary widely in structure and composition. Some may have gas giants, while others might be rocky planets or even systems with multiple stars. The study of these systems helps astronomers understand the formation and evolution of planets and the potential for life beyond our own.