Mare Serenitatis
| Photograph of Mare Serenitatis | |
| Coordinates | 28°00′N 17°30′E / 28.0°N 17.5°E | 
|---|---|
| Diameter | 674 km (419 mi) | 
| Eponym | Sea of Serenity | 
Mare Serenitatis /sɪˌrɛnɪˈteɪtɪs/ (Latin serēnitātis, the "Sea of Serenity") is a lunar mare located to the east of Mare Imbrium on the Moon. Its diameter is 674 km (419 mi).