The surface of the Moon is a battered and barren landscape. Its main features are vast volcanic plains and rugged mountain ranges. But its most common features are impact craters — bowl-shaped structures that formed when space rocks slammed into the lunar surface at high speeds.
Actually, not all of the craters were formed by rocks. A few dozen were formed by blobs of metal — spacecraft or rocket stages launched by the United States or Soviet Union. Some of the impacts were accidental, formed by probes that were out of control. Most were intentional, though, with some serving as parts of scientific experiments.
Some of the booster rockets and lunar modules that carried Apollo astronauts to the Moon, for example, were rammed into the surface to create “moonquakes.” Instruments that the astronauts left on the surface measured the quakes, providing important information about the Moon’s structure and composition.
And several craft have been aimed at the lunar poles. The impacts blasted up plumes of dust that scientists examined for particles of ice. The most recent of these impacts confirmed that ice does exist near the south pole.
The craters gouged by these impacts are too small to see from Earth, although several have been photographed by a Moon-orbiting spacecraft. But you can see the Moon itself tonight. It rises in late evening, with the bright star Regulus, the heart of Leo, the lion, rising above it.
Script by Damond Benningfield, Copyright 2013
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