8.03 understand why gravitational field strength, g, varies and know that it is different on other planets and the Moon from that on the Earth

An object’s gravitational field strength depends on its MASS. A massive object, like a star, will have a very large g-field. The Moon has less mass than the Earth, so its gravitational field is much weaker – approx 1/6^th of the Earth’s. This means that we could jump higher on the Moon, and objects would fall more slowly, as they experience a weaker gravitational force.

A planet with a large radius will have a weaker gravitational field at its surface, because the surface is further away from the centre of the planet.