Remarks The gravitational attraction between the Sun and objects on Earth is easily measurable and has been exploited in experiments to determine whether gravitational attraction depends on the composition of the object. As the exercise shows, the gravitational force on Earth due to the Moon is much weaker than the gravitational force on Earth due to the Sun. Paradoxically, the Moon’s effect on the tides is over twice that of the Sun because the tides depend on differences in the gravitational force across the Earth, and those differences are greater for the Moon’s gravitational force because the Moon is much closer to Earth than the Sun. Question Mars is about one and a half times as far from the Sun as Earth. To one significant figure, what is the gravitational force of the Sun on a 79.0 kg man standing on Mars? The mass of the Sun is 1.99 1030 kg.