This story was originally published on The Conversation as part of its Curious Kids series, in response to a young reader’s question about what happens at the military site. It appears here under a Creative Commons license. One of the reasons people can never be entirely sure about what is going on at Area 51 is that it is a highly classified secret military facility. It was not until 2013 that the United States government even acknowledged the existence and name “Area 51.” This information came out as part of…