"It's In Our DNA To Explore": NASA Joins Controversial Search For UFOs

Even if NASA has long explored the heavens, hunting for the origin, identity and purpose of a growing number of unexplained flying objects over planet Earth is bringing unprecedented challenges.

NASA on Thursday officially joined the search for UFOs -- but reflecting the stigma attached to the field, the US space agency kept secret for hours the identity of the person heading a new program tracking mystery flying objects.

The official's appointment is the result of a year-long NASA fact-finding report into what it calls "unidentified anomalous phenomena," or UAP.

"At NASA, it's in our DNA to explore -- and to ask why things are the way they are," agency chief Bill Nelson said.