A couple of days after First or Last Quarter Moon, train your telescope toward the eastern shores of Oceanus Procellarum. You’ll be treated to an impressive view of Kepler Crater and its complex ray system that spreads across the dark basaltic plains. The nearby terminator (the line that divides night from day) will advance 0.5° each hour, so you’ll need to work swiftly to render the scene before it changes significantly.
I start with black paper to represent the vast shadow area along the terminator, and I draw the sunlit features in white. You’ll need a sheet of black sketching paper (one suitable for pastels) attached to a clipboard, a stick of white hard pastel, a white pastel pencil, and a black charcoal pencil.
You’ll also want to add blending stumps of various sizes, cleaned and sharpened with sandpaper. Because the Moon is so bright, using a soft white light to see what you’re sketching won’t affect your dark adaption.
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