Sun

Sun is the star at the center of the Solar System. It is the closest star to Earth. The Sun is composed of hydrogen (about 74% of its mass, or 92% of its volume), helium (about 25% of mass, 7% of volume), and trace quantities of other elements.

diameter: 1,390,000 km.
mass: 1.989e30 kg
temperature: 5800 K (surface) / 15,600,000 K (core)