NASA has held its first public meeting on UFOs – officially referred to as “unidentified aerial phenomena” (UAPs) – a year after launching a study into unexplained sightings.

The space agency televised the four-hour hearing on Wednesday featuring an independent panel of experts who promised to be transparent. The team of 16 scientists and other experts selected by NASA included retired US astronaut Scott Kelly who spent nearly a year in space.

NASA said the focus of the public session at the agency’s headquarters in Washington, DC was to hold “final deliberations” before the team publishes a report, which panel chair David Spergel said was planned for release by late July.

“If I were to summarise in one line what I feel we’ve learned, it’s we need high-quality data,” Spergel said during opening remarks on Wednesday.

“The current data collection efforts about UAPs are unsystematic and fragmented across various agencies, often using instruments uncalibrated for scientific data collection,” Spergel said.

The team has “several months of work ahead of them”, said Dan Evans, a senior research official at NASA’s science unit, adding that panel members had been subjected to online abuse and harassment since they began their work.

The panel represents the first such inquiry ever conducted under the auspices of the US space agency for a subject the government once consigned to the exclusive and secretive purview of military and national security officials.

The NASA study is separate from a newly formalised Pentagon-based investigation of unidentified aerial phenomena documented in recent years by military aviators and analysed by US defence and intelligence officials.

The parallel NASA and Pentagon efforts, both undertaken with some semblance of public scrutiny, highlight a turning point for the US government after decades spent deflecting, debunking and discrediting sightings of unidentified flying objects – long associated with notions of flying saucers and aliens – dating back to the 1940s.

While NASA’s science mission was seen by some as promising a more open-minded approach to the topic, the US space agency made it known from the start that it was not leaping to any conclusions.

“There is no evidence UAPs are extraterrestrial in origin,” NASA said in announcing the panel’s formation last June.

“I want to emphasise this loud and proud: there is absolutely no convincing evidence for extraterrestrial life associated with” unidentified objects, panel member Evans said after the meeting on Wednesday.

US defence officials have said the Pentagon’s recent push to investigate such sightings has led to hundreds of new reports now under examination, though most remain categorised as unexplained.

The head of the Pentagon’s newly formed All-domain Anomaly Resolution Office has also said the existence of intelligent alien life has not been ruled out but that no sighting had produced evidence of extraterrestrial origins.

NASA’s Evans pointed out that the live stream of the meeting led to considerable trolling.

That comes on top of “online abuse” directed towards several committee members.

Harassment detracts from the scientific process and reinforces the stigma surrounding the topic of UAPs, said Evans, adding that NASA security is dealing with the issue.

“It’s precisely this rigorous, evidence-based approach that allows one to separate the fact from fiction,” he added. (Al Jazeera)

•PHOTO: A UFO display outside the Little A'Le'Inn cafe and motel, in Rachel, Nevada., the closest town to Area 51 - the secretive US Air Force base long associated with UFOs by enthusiasts of unexplained sightings [File: John Locher/AP]

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