‘Alien’ 12ft monolith which sparked mystery after appearing in Utah desert VANISHES after tourists flock to visit

 said they had managed to geo-locate the obelisk by closely studying the surrounding rock formations.

They claimed the bizarre structure was first captured on Google Earth in 2016.

However, some satellite images of the mystery monolith date back to around a year earlier.

And Lieutenant Nick Street, a spokesman for the local Department of Public Safety, said it's possible the structure has been there for "40, 50 years, maybe more." 

"It's the type of material that doesn't degrade with the elements. It may only be a few years old, who knows," he said.

"There's no real way based on the material it's made out of to tell how long it's actually been there."

The mystery has sparked a number of bizarre theories about how it got there — while some pointed to a more simple explanation.

Some say it closely resembles the work of artist John McCracken, who lived for a time in nearby New Mexico.

McCracken — who died in 2011 — was known for his freestanding sculptures in the shape of pyramids, cubes and shiny slabs.

Those who first spotted the oddball object last Wednesday said they were stunned by what they found.

"One of the biologists is the one who spotted it and we just happened to fly directly over the top of it," said pilot Bret Hutchings, who flew the chopper to help the wildlife officers count bighorn sheep in the area.

"He was like, 'Whoa, whoa, whoa, turn around, turn around!' And I was like, 'what,'" said Hutchings. "And he’s like, 'There's this thing back there — we've got to go look at it!'"

2001: A Space Odyssey?

When they turned around, they couldn't believe what lay before them: a shiny metal monolith seemingly sprouting out of the red earth.

"I'd say it’s probably between 10 and 12ft high," Hutchings estimated.

But the object sparked some eerie vibes — and lighthearted fun.

"We were kind of joking around that if one of us suddenly disappears, then the rest of us make a run for it," Hutchings joked.

Hutchings and his crew still have no idea how the bizarre object came to be there.

"We were, like, thinking is this something NASA stuck up there or something," Hutchings theorized.

"Are they bouncing satellites off it or something?"

They also guess that it could be a reference to a scene in a movie.

"I'm assuming it’s some new wave artist or something or, you know, somebody that was a big [2001: A Space Odyssey] fan," Hutchings said.

The exact location of the metal structure is remaining a closely guarded secret to stop hikers risking their lives travelling to the hard-to-access site.

"That's been about the strangest thing that I’ve come across out there in all my years of flying," Hutchings said.