Most of us still call them UFOs—unidentified flying objects. NASA recently adopted the term "unidentified anomalous phenomena," or UAP. Either way, every few years popular claims resurface that these things are not of our world, or that the U.S. government has some stored away.

Most of us still call them UFOs—unidentified flying objects. NASA recently adopted the term “unidentified anomalous phenomena,” or UAP. Either way, every few years popular claims resurface that these things are not of our world, or that the U.S. government has some stored away.