The mass is about 2 × 10 30 kilograms or 3 lakh 30 thousand times the mass of the earth. This mass is 99.6 percent of the total mass of the solar system. Hydrogen is the main constituent of the Sun , in fact three-quarters of the total mass is hydrogen. Helium is the second most abundant element after hydrogen. Elements heavier than helium are responsible for only 1.69% of the Sun's mass , yet their combined mass is 5,626 times the mass of the Earth. These heavy elements include oxygen , carbon , neon , iron, etc.