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View Full Version : How can we estimate the depth of a crater on the moon using the shadows?



martiansam
2012-Sep-23, 02:02 AM
I would figure one can estimate the depth of a crater based on the shadow it casts, probably using some trigonometry and some information on the location and time that crater exhibits on the moon. Any hints?

antoniseb
2012-Sep-23, 02:20 PM
Start with an assumption that the floors of the larger craters are flat. If you look at a time when the shadow of a particular mountain on the Eastern (or Western) edge of the crater has a particular low Sun angle (say 5 degrees), and see how long the shadow is, and then look again when the Sun angle is the other way, so the Sun angle is the same elevation, but in one case the shadow is on the crater floor, and in the other, it is outside the crater, it should be easy to measure the difference in shadow length, and then compute the difference in elevation of the floor of the crater and the surrounding terrain.