The far side of the Moon is often called the dark side. That's not because it gets any less sunlight than the near side. Instead, it's because we never see it. That hemisphere of the Moon always faces away from Earth, so the only way to see it is to fly behind the Moon. And that's just what a Russian spacecraft did 50 years ago today.
Luna 3 flew under the Moon's south pole, then swooped up around the farside, which at the time was basking in the sunlight.
The craft carried a 35-millimeter camera that snapped about 30 pictures. After an on-board laboratory processed the film, the pictures were scanned and transmitted to Earth. A British radio telescope intercepted the pictures and released them to the world.
Although they were crude and noisy by modern standards, the pictures caused a sensation. And they showed us that the farside is quite different from the nearside. Most of its surface consists of bright mountains and jumbled terrain. Only two dark volcanic plains were visible in the pictures. They were named the Sea of Moscow and the Sea of Dreams.
Since then, quite a few other craft have viewed the farside, giving us detailed maps of the Moon's "dark" hemisphere. Yet only 24 men have seen it with their own eyes -- the Apollo astronauts who orbited the Moon.
A modern-day lunar explorer is ready to get its own close-up view of the Moon -- a view that won't last long. We'll have more about that tomorrow.
Script by Damond Benningfield, Copyright 2009
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