What is the primary celestial body that defines our solar system?

The primary celestial body that defines our solar system is the Sun. The Sun contains about 99.86% of the total mass of the solar system and is the central gravitational anchor around which all the planets, including Earth, and other celestial objects orbit.

Its enormous mass creates a gravitational field that governs the motions of the planets, asteroids, comets, and other objects. The Sun also provides the necessary light and energy that sustain life on Earth and drive many of the dynamic processes on the various planets.

In contrast, while the Moon, Earth, and Jupiter are all significant celestial bodies, they do not serve as the central defining body of the solar system. The Moon is a satellite of Earth, Earth is just one of many planets, and while Jupiter is the largest planet in our solar system, it is still not as influential in defining the solar system as the Sun.