Hand-curated outlines of the major lunar maria (basaltic plains of the Moon's near side).
Coordinates are selenographic {longitude_deg, latitude_deg}, using
the convention where east is positive and west is negative — matching
the modern IAU standard and most contemporary lunar atlases.
All mare outlines are closed polygons, roughly traced from the lithological boundary visible in telescopic imagery. These are schematic — they capture the shape and approximate extent of each mare but not the coastline detail visible under high magnification.
Maria included
| Mare | Approximate center | Notes |
|---|---|---|
| Imbrium | 33°N, 17°W | Largest impact basin mare |
| Serenitatis | 28°N, 17°E | Apollo 17 landing area |
| Tranquillitatis | 8°N, 31°E | Apollo 11 landing area |
| Crisium | 17°N, 59°E | Isolated circular mare |
| Fecunditatis | -8°N, 51°E | Irregular southeast basin |
| Nectaris | -15°N, 35°E | Small southeast basin |
| Nubium | -21°N, -17°W | Southwest highlands border |
| Humorum | -24°N, -39°W | Small circular mare |
| Frigoris | 56°N, -15°W | Elongated northern band |
| Procellarum | 20°N, -55°W | Huge western "ocean" |
| Cognitum | -10°N, -23°W | Small mare, Surveyor 3 site |
| Vaporum | 13°N, 4°E | Small equatorial mare |
The northwest-negative / east-positive convention means that Mare
Imbrium's center (-17°W longitude) appears as -17 in the data.
Summary
Functions
@spec maria() :: [Bland.Basemaps.feature()]
Returns the list of lunar mare features.