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Moon Sliver

Photo: Sliver of the moon
A sliver of moon sits above a perfect cross-section of Earth's atmosphere, including rarely seen noctilucent clouds (top), wispy formations that appear about 50 to 60 miles (75 to 90 kilometers) above Earth's surface. This shot was captured by an astronaut aboard the International Space Station as the craft sailed over Mongolia in 2003.
Photograph courtesy NASA

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