Lunar X
clair-obscur effect in which light and shadow creates the appearance of a letter 'X' on the rim of the Blanchinus, La Caille and Purbach craters
en-GB/ˈluːnə ɛks/
en-US/ˈlunɚ ˈɛks/
clair-obscur effect in which light and shadow creates the appearance of a letter 'X' on the rim of the Blanchinus, La Caille and Purbach craters