月つきの海うみ

expression, noun

lunar mare; lunar sea

Astronomical term for the dark basaltic plains on the Moon's surface, formed by ancient volcanic eruptions. Often used in scientific or educational contexts.

• 月つきの海うみは、肉にく眼がんでも暗くらい模も様ようとして見みえる。

  The lunar maria are visible to the naked eye as dark patterns.

• 月つきの海うみは黒くろっぽく見みえる平へい原げんです。

  A lunar mare is a plain that looks dark.