9781422281420

Introduct ion

or as long as people have been on the Earth, they have looked beyond it.We look to the sky during the day and see the red-hot Sun. At night, the sky is busier, showing thousands of stars and the bright, glowing Moon. Beyond the stars lie dusty-looking galaxies and amazingly colorful nebulae. For millennia, however, people did not know what those lights really were. They made up stories or myths, but had little real evidence. F

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