It sounds like the opening scene of a conspiracy-theory movie. But it's real. US federal agents have swarmed onto a mountaintop observatory from a Blackhawk helicopter, ordering staff to leave and sealing the facility off from the public.

Perplexed astronomers and nearby residents have been wondering what is going on ever since.

The National Solar Observatory's operators have been given no word as to why it has been seized or when it will be returned to their hands again.

"We have decided to vacate the facility at this time as precautionary measure," observatory spokesperson Shari Lifson told the local Alomogordo Daily News. "The Association of Universities for Research in Astronomy who manages the facility is addressing a security issue at this time."


Nearby residences and facilities — including the local post office — have also been evacuated.

The FBI called on local police to help with the evacuation.

"There was a Blackhawk helicopter, a bunch of people around antennas and work crews on towers, but nobody would tell us anything," Otero County Sheriff Benny House said.

"We went up there and everything was good. There was no threat. Nobody would identify any specific threat. We hung out for a little while then we left. No reason for us to be there. Nobody would tell us what we're supposed to be watching out for."


The observatory is technically at Sacramento Peak, situated above the tiny town named Sunspot.

Sheriff House told media the agency had been in contact but refused to share any details.

"The FBI is refusing to tell us what's going on," said House. "We've got people up there that requested us to standby while they evacuate it. Nobody would really elaborate on any of the circumstances as to why."

He said he only had rumours to work with at this stage, including one that there had been a threat against the facility and staff, or a hazardous substances leak.


"If that's the case, why didn't they call us and let us deal with it?" he said. "I don't know why the FBI would get involved so quick and not tell us anything."

It's now been more than a week since the facility was seized and no explanation has been forthcoming.

The local newspaper, the Albuquerque Journal, has contacted the FBI. It refuses to confirm or deny that it is still in, or was even in, Sunspot.


The solar telescope inside the observatory is designed to track the Sun while photographing and collecting spectroscopic data on the rays it and its sunspots emit.

"The Sacramento Peak Observatory serves the solar physics community as the only high-resolution solar facility with extensive spectroscopic capabilities open for community access in the United States and as a development testbed for the high-order AO (adaptive optics) capability needed for the Daniel K. Inouye Solar Telescope," says a National Science Foundation description of the facility.

"The Association of Universities for Research in Astronomy (AURA) who manages the facility is addressing a security issue at this time," AURA spokesperson Shari Lifson said in a statement. "It's a temporary evacuation of the facility. We will open it up as soon as possible."

The observatory is not the only research facility in the mountainous region

The Apache Point Observatory is about 1km from the Sacramento Peak site. It remains in operation.

The Washington Post spoke to Professor James McAteer at New Mexico State University, asking him what had been happening at the facility.

He said AURA had "ordered the site vacated, providing no other reason than a "security" issue. He said the researchers did not spot anything in the sun to necessitate them leaving, nor were they aware of any scientific reason — such as an anomaly in the data they were collecting — for doing so."


The only clue is in the statement by AURA that the FBI's move relates to a "security issue".

This could imply espionage.

The National Solar Observatory's site enjoys a wide view over the US Air Force's Holloman Air Force Base and the US Army's White Sands Missile Range.

The observatory is covered with an extensive array of communications and sensor equpment.

Local police say they have seen officials inspecting the facility's towers and antennas.

"We don't know what they [the FBI] took, what their reason for being there was. We have no information on it," Sergeant Jon Emery, of the Otero County Sheriff's Office, told local television KOB 4. "We have no information on it." It is not clear if federal authorities have removed anything from the site, or, if they did, what it might have been.


In the absence of any official explanation from the FBI, internet conspiracy theorists have been put into overdrive.

Has the observatory found alien spacecraft?

Is a killer asteroid (or solar flare) about to hit Earth, and they don't want us to know?

Is this a secret government surveillance project?

Is the telescope being used as a secret laser weapon?

Has a secret substance broken loose?

Have the Russians hacked it?

News blackouts such as this offer prime doomsday and conspiracy potential.

And then there's the fact the site now appears to be abandoned.

One man has posted video to YouTube of how he simply drove up to the taped-off facility and walked around the deserted complex. And then, he spots a DVD of the X-Files, Unrestricted Access, placed prominently inside one of the buildings.


A drone has also been used to record the abandoned facility from overhead, and its footage uploaded.

But locals barred from re-entering their homes are nonplussed.

"It is very frustrating being out of our home. I will say that and I can't wait until this is over," Sean Williams told KOB4.

He hasn't been told when he will be allowed to return.

"My feeling is it's going to be something stupid and small and minuscule when it's all said and done but we will see," Williams said.

He's also heard about the conspiracy theories on the internet.

"Boy, people come up with some outlandish stuff," he said. "An alien landed here."

Professor McAteer stated the observatory has nothing to hide: "The telescope did not see aliens. The footage will be made public in its unaltered form. Nothing is hidden or kept secret."