(image available in print form)
The Figure simulates the Earth-Moon parallax using only the right triangles. Right triangles can be drawn in the lower half of the Earth to receive four more. The distances of the legs are the same as in the figure of lesson 1 for all right triangles. In order to save the figure in lesson 1 as the challenge problem to be solved at the end of this section scale down the numbers so that, for example, on paper, 1 inch will equal 1,000 km. (Also, the school textbook can supply additional data and consider that the Moon wobbles and is not always the same distance from the Earth.) Instruction can be presented by power point or using the overhead projector.