Most amateur astronomers know that the Moon's rugged surface can, when illuminated just right, produce amusing clair obscur effects: shapes and patterns formed by crater rims, mountain ranges and so on. The best-known of these can be seen when the terminator runs down the centre of the Moon's disc: the craters Blanchinus, La Caille and Purback form a large 'X', while crater Ukert and others produce a large 'Y' (or, some say, 'V'!)
No comments:
Post a Comment