designation for the so-called 'seas
' on the surface of the Moon
before modern telescope
s showed the dark areas to be dry plains. Since 1959 spacecraft probe
s and landings (both manned
and un-manned) have provided much detailed information
but their origin is still perplexing to scientists
The singular is Mare (e.g. Mare Imbrium), but there is a marked tendency to delatinize this terminology (e.g. Sea of Tranquility, Sea of Fertility etc).