My grandmother did not believe that a man could walk on the moon. Even as we sat, mesmerized, watching the television that momentous day, July 20, 1969, she kept repeating, “That’s not real. That’s not real.” Her worldview did not allow for the occurrence of such apparent impossibilities. But many people have no trouble believing that men have actually walked on the moon. We believe that future travellers to the moon will find mementos of those visits such as footprints, flags, and abandoned equipment, including a used car or two. History, if we choose to