Throughout human history, the moon has always been an unattainable dream for humans until July 20, 1969, when humans set foot on the moon. The sound of this short clip is the first sentence that Neil Armstrong said on the moon This is the fourth piece in the "A piece of time" series, which deals with the moment when humanity reached the moon. This is a window to the earth in our dream or in Armstrong's dream. A window in that dreamy moment connects a seemingly lifeless land with a land full of life.