The Sun is big, really big. It is the biggest part of the solar system. It takes up over 99.8 percent of the mass in the solar system [that's one big ball of gas]. It is not named after a Roman god, like most of the planets, but its origin is thought to be similar to the name the ancient Romans gave it: "Sol". Sol was the god of [surprise, surprise] the Sun [surprising, huh?].
Composition
The majority of the Sun is the gas hydrogen. Hydrogen makes a 75 percent of the Sun. In an incredibly distant second is helium. Helium makes up about 25 percent of the Sun. The rest of the components in the Sun are metals; these metals make up less than a tenth of a percent of the total mass of the Sun. Over time, the balance will change; going from a higher amount of helium than hydrogen. This is because the hydrogen in the Sun gradually changes into helium and energy. In fact, over time, the Sun is going to get lighter in weight because of this transition.
Uniqueness
The Sun has many differences from the Earth [outside of the obvious]. The rotation of the Sun on the surface is not stable. It is a different speed in different areas. At the equator of the Sun, the surface rotates once at about ever 25 ½ days, while at each of the poles, the rotation speed can get to as slow as 36 days for one rotation. The core on the other hand has a very stable rotation, similar to that of Earth being as it is more like a solid body like Earth (the gas giants have a similar problem).
The Sun rules over the planets (in a sense) and other bodies in the solar system, it is the biggest part of the solar system and contains the majority of the mass in the solar system. The Sun is a ball of gas that can get to extreme temperatures getting up to 5800 K on the surface of the sun and about 15.6 million K in the core of the Sun [that's-a one hot-a tamale]!
