Back in the 1950s, if you saw an unidentified flying object, you could fill out one of the U.S. Air Force’s handy UFO questionnaires for Project Blue Book. That government program dissolved in 1969, but the military has remained interested in UFO sightings ever since. In April 2019, the U.S. Navy confirmed it is updating its guidelines for how pilots and personnel should report what it calls “unexplained aerial phenomena,” or UAP.

“There have been a number of reports of unauthorized and/or unidentified aircraft entering various military-controlled ranges and designated air space in recent years,” the Navy said in a statement to POLITICO, the first outlet to report the news. “[T]he Navy is updating and formalizing the process by which reports of any such suspected incursions can be made to the cognizant authorities.”

Basically, the Navy wants to create a formal process for pilots and other personnel to report flying objects they can’t explain so that someone can investigate. The Navy seems less concerned that UAPs are a sign of alien life, and more concerned that they’re unauthorized aircrafts from a foreign nation. This is why the U.S. started investigating UFO sightings in the late 1940s, too: there was concern that people were actually spotting secret Soviet planes.

READ MORE: Seen a UFO? In the ‘50s, You Could Report It In This Easy Questionnaire

The Navy’s announcement about its UAP reporting guidelines comes a year and a half after The New York Times revealed the Pentagon had a secret Advanced Aerospace Threat Identification Program from 2007 to 2012. Luis Elizondo, the former Pentagon official who led the classified program and is featured in HISTORY’s new show Unidentified: Inside America’s UFO Investigation, resigned because he felt the Pentagon wasn’t doing enough to identify and combat UAPs. Elizondo has said he thinks they could be a threat to national security. (Unidentified: Inside America’s UFO Investigation premieres on May 31 on HISTORY.)

The short-lived Advanced Aerospace Threat Identification Program was able to run as long as it did because it had support from prominent members of Congress like Senator Harry Reid. Similarly, the Navy’s recent UAP updates may have been a response to Congressional interests in tracking them.

“In response to requests for information from Congressional members and staff, Navy officials have provided a series of briefings by senior Naval Intelligence officials as well as aviators who reported hazards to aviation safety,” the Navy said in its statement to POLITICO. It did not, however, identify which members of Congress had requested the briefings.

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