Mass, Weight and Gravity

The gravitational field strength of a planet measures how much a 1kg mass weighs on the surface of a planet. It is measured in Newtons per Kg (N/Kg)

Weight = Mass * Gravitational Field Strength

N = kg * N/kg

E.g. How much did Neil Armstrong weigh on the moon?

Mass of Neil = 80kg

Moon GFS = 1.6 N/Kg

W = M*GFS = 80*1.6 = 128N = 12.8kg