(A) The global total reflectance at 321 nm wavelength from the LROC/WAC instrument. (B) Total latitudinal average of 321 nm reflectance with a standard deviation envelope. (C) Only the mare regions of the global reflectance at 321 nm wavelength. (D) Maria reflectance latitudinal average with a standard deviation envelope. (E) Only the highland regions of the global reflectance at 321 nm wavelength. (F) Highlands reflectance latitudinal average with a standard deviation envelope. Horizontal dashed lines mark the ±55° feature in the right column.