The belief in aliens visiting Earth via spacecraft was given greater validity last year following reports by both The New York Times and Politico Magazine of the secretive Advanced Aviation Threat Identification Program (AATIP).
This was coupled with a video released by the Department of Defence which shows a two Navy F/A-18F fighter jets and an unknown object near San Diego.
But, some experts in UFO studies think the release was merely a test to gauge public reactions to set people up for really big news about aliens.
Retired nuclear physicist and a long-time investigator and lecturer on the UFO phenomenon, Stanton Friedman, said: "I can't say I know why things are coming out at this time.