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A highly anticipated US government report on UFOs (unidentified flying objects) is due to be released before the end of June. Here's what we know so far.
The unclassified report was demanded by Congress after numerous reports from the US military of vehicles seen moving erratically in the sky.
It also follows a cultural shift that saw the US military and US political leadership go from extraterrestrial-sceptic to ET-curious.
But with little conclusive evidence expected to confirm any intergalactic visitations, it remains to be seen whether any earthling minds will change.
Military leaders warn that the technology, if not alien, may belong to US adversaries such as Russia or China.
media captionThe Pentagon said it released three clips to "clear up any misconceptions"What do we know about the report?
Last August, the Pentagon established the Unidentified Aerial Phenomena Task Force to look into observations of unknown flying aircrafts.
The group's job is to "detect, analyse and catalogue" these events, as well as to "gain insight" into the "nature and origins" of UFOs, the Pentagon said.
A classified version of the group's report was provided to lawmakers earlier this month. Unnamed officials told US media that the report found no evidence of alien activity, but also did not rule it out.
Notably, the task force also reportedly established that the observed UFOs were not secret US military technology.
Officials examined over 120 incidents from the past two decades, including three videos that the Pentagon declassified last year and described as showing "unexplained aerial phenomena".
Although no earth-shattering revelations are expected, the existence of a government report on an much-ridiculed issue shows how UFOs have beamed out of the realm of purely science fiction pop culture and into the world of US national security.
GettyMovements that are hard to replicate, that we don't have the technology for or are travelling at speeds that exceed the sound barrier without a sonic boom.John Ratcliffe
Former US Director of National Intelligence Why do we care now?
Public pressure on the US to release what it knows about aliens has been building for decades as civilian groups of so-called ufologists argue that evidence of their existence has been suppressed by the government.
The Pentagon has been quietly gathering data since 2007 as part of the military's little-known Advanced Aerospace Threat Identification Program.
Money for the programme came at the request of Nevada Senator Harry Reid, a Democrat who represents the region that encompasses Area 51 – the military site where conspiracy theorists believe remains collected from an alien crash in the town of Roswell have been studied since 1947.
image copyrightGetty Imagesimage captionObjects in the sky photographed in Massachusetts in 1952
Former top officials and even US presidents have recently weighed in on whether the truth truly is out there.
Hillary Clinton's campaign manager John Podesta, long a follower of UFO theories, promised during her 2016 campaign that she would release classified government reports on aliens if she were elected.
In an interview last year, then-President Donald Trump said he would not disclose – even to his family – what he had learned about aliens.
"I won't talk to you about what I know about it, but it's very interesting," he said.
BBCIt was travelling very fast and very erratically and we couldn't anticipate which way it was going to turn or how it was manoeuvring the way that it was.Alex Dietrich
Former US Navy pilot
Former President Barack Obama put it more plainly in May, when he told late night TV host James Corden: "When I came into office, I asked… is there the lab somewhere where we're keeping the alien specimens and space ship? And you know, they did a little bit of research and the answer was no."
"What is true, and I'm actually being serious here, is that there are, there's footage and records of objects in the skies, that we don't know exactly what they are," Mr Obama continued.
"We can't explain how they moved, their trajectory… And so, you know, I think that people still take seriously trying to investigate and figure out what that is."
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The effort to release what is known about UFOs has also found followers in Congress – both Republican and Democrats – who argue that the report will end the stigma that may prevent troops from telling a superior officer about an unexplainable encounter.
What evidence is there?
Other US military and intelligence officials have detailed the odd sightings, with some of the more credible reports coming from pilots who have personally observed UFOs near military weapons and training facilities from within their cockpits.
In March, Mr Trump's former director of national intelligence John Ratcliffe – who previously oversaw all 18 US intelligence agencies – summarised the phenomena, telling Fox News: "Frankly, there are a lot more sightings than have been made public."
"We are talking about objects that have been seen by Navy or Air Force pilots, or have been picked up by satellite imagery, that frankly engage in actions that are difficult to explain.
"Movements that are hard to replicate, that we don't have the technology for or are travelling at speeds that exceed the sound barrier without a sonic boom."
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In a CBS News 60 Minutes episode last month, two former Navy pilots discussed seeing an object in the Pacific Ocean that appeared to mirror their movements.
One pilot described it as a "little white Tic-Tac-looking object", referring to the white oblong mints.
"And that's exactly what it looked like, except it was traveling very fast and very erratically and we couldn't anticipate which way it was going to turn or how it was manoeuvring the way that it was, or the propulsion system," witness and former Navy pilot Alex Dietrich told BBC News.
"It didn't have any apparent smoke trail or propulsion. It didn't have any apparent flight control surfaces to manoeuvre in the way that it was manoeuvring."
What are other countries doing about UFOs?
Former Senator Reid has defended the $22m (£16m) he had obtained for the original UFO programme at the Pentagon, saying that other countries were also studying the issue.
"We know that China is doing it," he told Nevada Newsmakers in 2019. "We know that Russia, which is led by someone within the KGB, is doing it, too, so we better take a look at it, too."
Research done by the US Defence Department "showed that not two people, four people or six people or 20 people but hundreds and hundreds of people have seen these things, sometimes all at the same time," he argued.
image copyrightGetty Imagesimage captionUFO sightings have long been a subject of fascination in the US
Last December, the former head of the Israeli space directorate at the country's defence ministry told a local newspaper that Mr Trump was on the "verge of revealing" the existence of an intergalactic treaty, but pulled back out of fear of inciting a "mass hysteria".
"There is an agreement between the US government and the aliens," Haim Eshed told the Yediot Aharonot newspaper. "They signed a contract with us to do experiments here."
The far-fetched statement has not been confirmed – by man nor Martian.