The Sun is the at the center of the . It is almost perfectly spherical and consists of hot interwoven with . It has a diameter of about 1,392,684 km (865,374 mi), around 109 times that o, and its mass (1.989 kilograms, approximately 330,000 times the mass of Earth) accounts for about 99.86% of the total mass of the Solar System. Chemically, about three quarters of the Sun's mass consists o while the rest is mostly . The remainder (1.69%, which nonetheless equals 5,600 times the m.