For centuries, people have witnessed unexplained lights in the sky and thought that perhaps they might be ghosts or angels. However, it was in the summer of 1947 when a different explanation became popular. Following a widely reported incident over Mt. Rainier in Washington state, people began to believe that these unidentified flying objects (UFOs) are actually alien spacecraft prowling the Earth.


원문출처 : https://www.cnn.com/2019/06/21/opinions/pilots-seeing-ufos-opinion-lincoln/index.html