The Blue Marble

The Blue Marble is a famous photograph of the Earth taken on 7 December 1972 by the crew of the Apollo 17 spacecraft at a distance of about 29,000 kilometres or about 18,000 statute miles. It is one of the most widely distributed photographic images in existence. The image is one of the few to show a fully lit Earth, as the astronauts had the Sun behind them when they took the image. To the astronauts, Earth had the appearance of a child's glass marble (hence the name).
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