Lunar Maria - Sea of Rains

Lunar Maria - Sea of Rains

Courtesy of NASA/JPL

http://solarsystem.nasa.gov/multimedia/display.cfm?IM_ID=793


The maria (singular = mare) are the dark areas you see when looking at the Moon. These maria or "seas" make up about 16% of the Moon's surface, but are 30% of the Earth-facing side.

The Sea of Rains is the Moon's largest, well-preserved basin. This view looks south across the Sea of Rains toward Copernicus Crater (near the horizon). The crater near the center of the image is Pytheas (20 km in diameter). The Sea of Rains appears smooth due to the lava flows that covered the area following impacts. It is peppered with secondary crater chains and elongated craters.