Page 47 - Curriculum Visions Dynamic Book

 This is an angled view of the lunar far side from the Apollo 16 spacecraft. Among other craters the largest, just above center left, is the Leonov Crater.
basin A large depression in the ground (bigger than a crater).
lava Hot, melted rock from a volcano.
mare (pl. maria) A flat, dark plain created by lava flows. They were once thought to be seas.
ray A line across the surface of a planet or moon made by material from a crater being flung across the surface.
reflective To bounce back any light that falls on a surface.
Far side of the Moon
Rather extraordinarily, in contrast to the near side, the far side consists of mainly cratered highlands with very small areas of mare. Lava has not flowed out and covered the crater bottoms on the far side in the same way as it has on the near side. This contrast remains to be explained.
How the Moon reflects light
The Moon appears to shine brightly. But in fact, it is nowhere near as reflective as the Earth, bouncing back only a small amount of the sunlight that falls on it.
The craters and the great roughness of the ground, in general, have a strange effect on the way the Moon reflects light. When the Moon is full, it reflects light to us 11 times more strongly than when it is at half Moon, even though a difference of only two times would be expected. This is explained by the fact that the Moon’s face is covered with deep craters. We suddenly see an increased brightening as full Moon approaches, and light is also reflected from the bottoms of the craters.
47