Sun

The Sun is about 109 times wider than Earth and holds 99.8% of the solar system's mass.

The Sun is a G-type main-sequence star at the center of the solar system, born about 4.6 billion years ago from a cloud of gas and dust. Its visible surface is about 5,500°C while the core reaches roughly 15 million °C, where hydrogen fuses into helium. At about 1.39 million km across it is 109 times wider than Earth, and in roughly 5 billion years it is expected to swell into a red giant that engulfs Mercury and Venus.