Deep in the Mars-like landscape of Utah’s red-rock desert lies a mystery: A gleaming metal monolith in one of the most remote parts of the state. And to date, no one know what it is or how it got there – and now, how it disappeared.

Recalling the monolith that appears in the Stanley Kubrick movie “2001: A Space Odyssey,” the smooth, tall structure was found during a recent helicopter survey of bighorn sheep in the southeastern part of the western state.

A crew from the Utah Department of Public Safety and Division of Wildlife Resources spotted the gleaming object from the air Nov. 18 and landed to check it out during a break from their work.

They found the three-sided stainless-steel object is about as tall as two men put together. But they discovered no clues about who might have driven it into the ground among the undulating red rocks or why.

“This thing is not from another world,” confirmed Lt. Nick Street of the Utah Highway Patrol, part of the Department of Public Safety.

Still, it’s clear that it took some planning and work to construct the three- to four-metre monolith and embed it in the rock.

The exact location was so remote that officials were not revealing it publicly, worried that people might get lost or stranded trying to find it and need to be rescued.

However, on the weekend it was found anyways – and removed, less than 10 days after being discovered.

Reporters with The Salt Lake Tribune hiked to the spot on Saturday and confirmed that it was gone.

Spencer Owen of Salt Lake City said he saw the monolith Friday afternoon and camped in the region overnight, but as he hiked to the area again on Saturday people passing him on the trail warned him it was gone, the Tribune reported. When he arrived at the spot, all that was left was a triangular piece of metal covering a triangular-shaped hole in the rocks.

“I was really bummed,” said Owen, who posted a video on his Instagram. “It was so pretty and shiny. I wanted to go see it again.”

Riccardo Marino and his girlfriend Sierra Van Meter were travelling from Colorado to California and decided to stop and see the object after finding the GPS coordinates online.

“This was just a once-in-a-lifetime experience that we couldn’t miss out,” Marino said.

On the way, they passed a long-bed truck with a large object in the back and he said he joked, “Oh look, there’s the Utah monolith right there,” he said.

When they arrived at the spot, it was gone.

State officials confirmed that they were not responsible.