Which celestial body has the largest diameter in our solar system?

The Sun is the celestial body with the largest diameter in our solar system, measuring about 1.4 million kilometers (approximately 864,000 miles) across. In contrast to Earth, which has a diameter of about 12,742 kilometers (7,918 miles), the Moon at roughly 3,474 kilometers (2,159 miles), and Jupiter, the largest planet, which has a diameter of about 139,822 kilometers (86,881 miles), the Sun vastly surpasses them all in size.

The Sun makes up about 99.86% of the total mass of the solar system and is the central star that holds the system together with its immense gravitational pull. This sheer size and mass are critical for the dynamics and stability of the orbits of all the other bodies within the solar system. Understanding the scale of the Sun helps illustrate the relative sizes of planets and moons in our solar system, revealing just how small they are in comparison.