Page 3 - 11.1 THE MOON INTRODUCTION

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• The Moon is thought to have formed about
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4.51 billion years ago, not long after Earth.
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• The Moon is in synchronous rotation with Earth,
a n d th u s a l w a y s s h o w s th e s a m e s i de to E a r th ,
and thus always shows the same side to Earth,
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the near side. Because of liberation, slightly
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more than half (about 59%) of the total lunar
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s u r fa ce ca n b e vi e w e d fr o m E a r th .
surface can be viewed from Earth.
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• After the Sun, the Moon is the second-
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brightest celestial object regularly visible in
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Earth's sky.

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• Its surface is actually dark, although compared
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to the night sky it appears very bright, with
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a reflections of suns light.
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