* Mare is Latin for "sea".
* The name is a bit misleading, as the maria are not actually filled with water, but rather vast plains of solidified volcanic basalt.
* They were named "seas" by early astronomers who thought they were bodies of water.
Here are some additional details:
* Formation: The maria formed billions of years ago from massive volcanic eruptions that filled the lunar basins.
* Appearance: They appear darker than the surrounding lunar highlands because the basalt reflects less sunlight.
* Examples: Some of the most prominent maria include Mare Tranquillitatis (Sea of Tranquility), Mare Serenitatis (Sea of Serenity), and Mare Imbrium (Sea of Rains).
