Trivial Tuesday

Here we are again, gathered together to try to answer another trivia question.  In two weeks we will observe the 40th anniversary of the moon landing.  As we all know, Neil Armstrong was the first man to walk on the moon.  This week's trivia question is similar.
Who was the last man to walk on the moon?  That is, the last man to have his feet on the surface of the moon.  He is American.
Good luck with this one and have a good day.