Earth/Moon gravitational field

Learning objectives

To apply the superposition principle to determine the gravitational field at any point between the Earth and the Moon.
To show how much stronger the earth's field is compared to that of the Moon.

Gravitational fields (and force!) obey the principle of superposition. You can show that the field follows a spherical symmetry near the planets but the influence of the Earth extends farther because of its superior mass (80 times Moon's mass).
Notice the existence of a single point where the g field is equal to zero.
Click on the screen to show or erase the field lines.
This animation is not to scale.