The Pentagon on Friday released a second tranche of videos and documents of unidentified aerial phenomena (UAP) – or UFOs – answering few questions about the existence of alien life but fueling what has quickly become a ratings winner for the White House.

The first reveal earlier this month of 162 files of previously secret or rarely seen accounts of UAP sightings received more than a billion hits on the government website set up to house them, according to a press release from the war department, the Trump administration’s preferred term for the Department of Defense.

Friday’s release, also stretching back decades, features a further 50 videos and documents, including first-hand testimony from civilians and military members.

In one video from the Middle East in 2019, taken “likely from an infrared sensor aboard a US military platform operating within the US Central Command area of responsibility”, according to the Pentagon, three UAP are captured flying in formation over the Persian Gulf.

Another formation of four unidentified objects is seen flying past vessels on the water off Iran in a video from 2022.

Footage taken over Syria in 2021 shows a mysterious object racing away at speed akin to instantaneous warp-speed acceleration from science fiction movies.

Few of the objects seem to resemble flying saucers, discs or other traditionally perceived forms for UAP, although one October 2022 clip taken at an undisclosed location shows a cigar-shaped entity racing over what appears to be a residential area.

None of the videos are accompanied by explanations, and the Pentagon’s all-domain anomaly resolution office (AARO) has previously stated it has no evidence to suggest any of the thousands of objects seen on video, or described in written testimony, is of extraterrestrial origin.

In its 8 May release, a statement from the defense department said the public “can ultimately make up their own minds about the information contained in these files”.

Additionally, the information is collated from a diverse range of sources, including government agencies including several military branches, the FBI, the state department and Nasa. “Many of these materials lack a substantiated chain-of-custody,” the Pentagon notes.

Even so, Friday’s release is likely to provoke further debate about a subject that has fascinated humankind for generations, and prompted decades of conspiracy theories about government cover-ups and secrecy about what it knows.

In February, Donald Trump directed the release of government files related to UAP and the possibility of extraterrestrial life, citing “tremendous interest” in the topic but adding he did not know personally if aliens were real or not.

Polling suggests most Americans believe aliens exist, and half think they have visited Earth.

The Pentagon on Friday said it was working on a third release of UAP files, which it said would announce “in the near future”.

New Nasa recordings are included in the second batch, including astronaut descriptions of mysterious objects and bright lights similar to those reported by Apollo 11 crew member Buzz Aldrin in the first release this month.

In one clip, Wally Schirra, the sole astronaut on Mercury-Atlas 8 that orbited the Earth six times in October 1962, told mission control he saw “little white objects that seem to come from the capsule itself and drift off”.

He also spoke of a burst of light in the window, whose source he said he could not identify, although he noted it appeared just as the sun passed below the horizon.

Astrophysicist Neil deGrasse Tyson, on his YouTube channel StarTalk, said it was “a little misleading” for Nasa files to be included in the Pentagon releases.

“Nasa spends time in space, and if an alien is going to come from anywhere, it’s probably going to be from space, I get that,” he said.

“But those Nasa documents were never classified, and what the astronauts were seeing would have a complete, full, rational explanation. The fact they are released juxtaposed with other files where people see unidentified anomalous phenomena, and don’t know what it is, then it’s almost guilt by association.”

Tyson said aliens were “kind of low on my list” as an explanation for UAP.

“In the history of science, the correct explanation has never been magic, or aliens, ever,” he said.

“I’m just sitting back waiting for you to walk out the alien – that’s kind of what I need right now, and then we’re good.”