How will you ‘weigh the sun’, that is estimate its mass? The mean orbital radius of the earth around the sun is 1.5 × 108 km
Orbital radius of the Earth around the Sun, r=1.5×1011 m Time taken by the Earth to complete one revolution around the Sun, T=1 year=365.25 days =365.25×24×60×60s Universal gravitational constant,G=6.67×10−11 Nm2kg−2 Thus, mass of the Sun : M=GT24π2r3 =6.67×10−11×(365.25×24×60×60)24×3.142×(1.5×1011)3 ≈2×1030 kg Hence, the mass of the Sun is 2×1030 kg
