AS15-2503 (M)

Figure 21

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 Click here for nearside lunar chart showing location
 Click here for farside lunar chart showing location

This view, one of the most southerly photographed by the Apollo astronauts, straddles the boundary between near and far sides and shows terrain typical of both sides. In the foreground is densely cratered terra or highland terrain typical of the far side. At the top of the picture a large area is covered by mare material, which is easily distinguished from the terrae by its smooth appearance and darker color. This mare area, appropriately named Mare Australe (Southern Sea), occupies a large old circular basin - probably a gigantic impact scar. The rings and arcuate segments of rings projecting through the mare are the rim crests of smaller craters that were created after the basin was formed but before it was filled. On the far side otherwise similar old basins have less mare filling or none, whereas most circular basins on the near side are deeply flooded by mare material.    D.E.W