The familiar Sea of Tranquility (Mare Tranquillitatis) is the blue area right of center.
White lines radiate from the crater Tycho at bottom left, while purplish tones mottle the crater Copernicus left of center.
Though exaggerated, the different colors are recognized to correspond to real differences in the chemical makeup of the lunar surface - blue hues reveal titanium rich areas while orange and purple colors show regions relatively poor in titanium and iron.