- The lunar maria (/ˈmæri.ə/ MARR-ee-ə; sg. mare /ˈmɑːreɪ, -i/ MAR-ay, MAR-ee) are large, dark, basaltic plains on Earth’s Moon, formed by lava flowing into ancient impact basins. They were dubbed maria (Latin for ‘seas’) by early astronomers who mistook them for actual seas.[citation needed] They are less reflective than the “highlands” as a result of their iron-rich composition, and hence appear dark to the naked eye. The maria cover about 16% of the lunar surface, mostly on the side visible from Earth. The few maria on the far side are much smaller, residing mostly in very large craters. The traditional nomenclature for the Moon also includes one oceanus (ocean), as well as features with the names lacus (’lake’), palus (‘marsh’), and sinus (‘bay’). The last three are smaller than maria, but have the same nature and characteristics.
- Star Tales - Ara (ianridpath.com)
Altars feature frequently in Greek legend, for heroes were always making sacrifices to the gods, so it is not surprising to find an altar among the stars. But this altar is a special one, for it was used by the gods themselves to swear a vow of allegiance before their fight against the Titans, according to Eratosthenes and Manilius. That clash, known as the Titanomachy, was one of the most significant events in Greek myth.