Geometry and the height of the mountains on the moon

Galileo's image of the moon
Galileo's map of the moon.

Galileo Galilei matched careful observation of sunlight and shadows on the moon, with some beautiful geometry to estimate the height of lunar mountains, in 1609. He needed the Pythagoras’ Theorem and the quadratic formula, both of which middle school students should be familiar. Larry Phillips has a nice post describing how Galileo did the math. The image below (from Pioneers of Science shows how to get started.

From the Gutenberg Project eBook of Pioneers of Science by Oliver Lodge.

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