As we look forward to a major lunar event on Sunday night -- the supermoon lunar eclipse -- it's time to take a look back at how our understanding of Earth's only (permanent) natural satellite has changed since the dawn of the Space Age.
In the more than four decades since humans walked on the moon, a heck of a lot has changed. We've changed space programs and vehicles a few times, expanded our horizons to international missions, and sent spacecraft across the solar system. For about 20 years, NASA didn't look much at the moon, but we've been back in a big way in the past 10 years watching it with the Lunar Reconnaissance Orbiter (LRO).
In those years of observations, we've learned the moon isn't quite the cold, dead world we thought it was when the Apollo astronauts put bootprints on its surface between 1969 and 1972. This isn't your grandparents' moon. Here is some of the cool new stuff we've learned.