UFOs… Is the truth out there?

Have we been visited by space aliens? This month space boffins Sue Nelson and Richard Hollingham delve into the history and science of Unidentified Flying Objects (UFO) or Unidentified Anomalous Phenomena (UAPs) as they’re now known. They discuss UFOs with professor of history and bioethics at Pennsylvania State College and author of After the Flying Saucers Came, Greg Eghigian. They also talk to Thomas Zurbuchen, the longest ever serving head of science at NASA who commissioned an official report on UFOs. What does he believe?