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The Moon As We Know It
As our closest cosmic neighbor, and the Earth's only natural satellite, the moon has long been a symbol of mystery and intrigue. Spacecraft have been studying the moon for nearly 50 years, and lunar exploration has been an important benchmark in our nation's history. But, there is still much to learn, and many more questions to answer. Currently, NASA's only active mission at the moon is the Lunar Reconnaissance Orbiter, which launched in June 2009. Here is a look at the moon as we know it.