UFOs: the truth is out there
If you've ever wondered whether aliens exist, you can now rest knowing the truth is out there… on the Web, that is. Blogger and UFO researcher, John Greenewald, has made nearly 130,000 files publicly available via The Black Vault.
The files were all part of "Project Blue Book."
Until now, they have only been available at the national archive in Washington, DC - or not at all publicly. Greenewald obtained some of the images through freedom of information requests.
Run by the United States Air Force (USAF), Project Blue Book's stated mission was to scientifically analyze evidence of unidentified flying objects, and determine whether they were a threat to national security.
From 1947 to 1969, the project examined more than 12,000 incidents - and came up with explanations for the vast majority.
Although the project ended without any conclusive evidence of extraterrestrial life, around 700 of the incidents remain unexplained.
With the release of these documents, you can try to decide for yourself.
We've collected some of the most intriguing images from the newly public vault here.
This image is from the Lubbock Lights incident, named after the location in Texas where it took place. Seen and documented over two months in 1951, the incident was regarded as one of the first great UFO cases in the United States.
The USAF came to the conclusion that the lights in the sky were reflections of streetlights on plovers - a bird with a white breast - flying in formation.
Many sightings thought to be UFOs are put down to natural phenomena - often the weather.
In this photo from New Zealand in the winter 1951, a lenticular cloud is visible low in the sky. Winds form lenticular clouds into a lens shape in the high upper atmosphere, often above a mountain or hill. Time and again, lenticular clouds are mistaken for UFOs.
Could this enigmatic light - surrounded by what appear to be flying umbrellas - be a sign of intelligent life in the universe? UFO researcher Andrew Hennessey told DW the image could be of "aircraft landing lights, or Venus, or specialized military aircraft."
The light in question was eventually determined to have been the star Arcturus. But the difficult-to-make-out nature of the image adds to a sense of mystery.
Some of the images appear to be pure fantasy, such as this apparent submarine cutout floating over the White House.
"This looks like a fake, showing the cultural expectations of a UFO shape of the 1950s," says Hennessey.
While Hennessey says many UFO sightings turn out to be natural phenomena - or fakes - they cannot be ascribed only to human imagination.
"There's too rich a folklore record to say it's merely a psychological phenomenon," Hennessey says. "The explanations aren't always easy."
This excerpt from the famous Hottel Memo (above) is not from the vaults of the USAF but from the US Federal Bureau of Investigation (FBI).
It's among the most popular of the FBI's public documents available online, with almost a million hits.
Paranormal enthusiasts point to it as strong proof of knowledge about the existence of intelligent extraterrestrial life.
The flying saucers and petite humanoid bodies mentioned in the 1950 document have been speculated to be linked to the infamous Roswell incident in New Mexico, one of the most famous - and to some, least clarified - UFO incidents on record.
"The Hottel Memo is consistent with thousands of years of human archaeological evidence of non-human beings and their alleged technologies," says Hennessey.
But Hennessey says Project Blue Book "may well have been just an exercise in public relations rather than a serious scientific examination."
"It may well have been covering up the tracks of research and development into exotic technology, which the military were very much into," Hennessey says. Or it may have been covering up evidence of aliens, he adds.
So perhaps we're not alone in the universe, after all?
"It's beyond a doubt," says Hennessey, "I've got pictures."