Moon's distance as given by the Earth's shadow
Measuring the distance to the Moon by this method requires finding two values first---namely, the angular radius of the Moon's disc and the angular radius of the Earth's shadow (where it cuts the Moon), and then using these values in the relevant equation, which in this illustration is either the equation for the distance L (in Earth radii e) between the centre of the Earth and the centre of the Moon's disc, or the distance M (in Earth radii e) between the centre of the Earth and the centre of the Moon's spherical body. On average, the difference between M and L is just about 3660 metres, which, for most purposes is negligible.