Today is "National Moon Day." It was 51 years ago today, July 20th, 1969 that Neil Armstrong became the first man to walk on the moon. Some believe that it was a hoax but that's a story for another day.

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Apollo XI was a crew of three: Neil Armstrong, Edwin "Buzz" Aldrin and...Michael Collins. Nobody can remember Michael's name. I feel bad for him.

Here are some moon facts to impress your friends with today:

In square miles, the total surface area of the Moon is smaller than in Asia. The Moon is 14.6 million square miles. Asia is 17.2 million.

Shadows are darker on the Moon then they are on Earth. It's because there's no air or atmosphere on the Moon to scatter direct sunlight. On Earth, light bounces off tiny particles in the air. That doesn't happen on the Moon.

The word "lunatic" literally means "moon sick." Doctors used to think full moons made people crazy, so they called them lunatics. Ask any ER nurse or doctor and they'll tell you they think the full moon does make people do crazy things.

Here's your final Moon Day fact. Neil Armstrong's famous quote may have been a misquote. His immortal words were "That's one small step for man, one giant leap for mankind." But is that what he said?

Communication was lost for a split second between "for" and "man." He apparently said, "That's one step for [a] man, one giant leap for mankind." You be the judge if he said [a] or not here.

It's also rumored that he said "Moonwalk?, I'll show you a moonwalk!!! Okay, that one is not true.

I was four years old, so I don't remember that special event. What do you remember about that day?

[via National Today/Space.com/Universe Today/Wikipedia]