The moon carved into the door of the outhouse was an ancient symbol. The moon means luna. It was carved in the door in the colonial and frontier times to denote that it was the outhouse for woman. The starburst was carved into the outhouse that was for men. The mens outhouse became a thing of the past because of disrepair and cleanliness and eventually only there was only the outhouse with the moon and both sexes used it. The moon also did let in a little light, both from the sun in the day time and the moon at night. The moon if left open also did let in a little ventilation. The outhouse was not usually very tightly built so there were other means of air circulation. As a child we had an outhouse, however ours did not have a carved opening in the door. I hope this answers the question you have. Lucy