Last photo developed 50 years after 'mysterious' death of two mountain climbers sheds new light on case

In 1973, Janet Johnson and John Cooper embarked on an expedition up Mount Aconcagua - but they never made it home.

Janet, a schoolteacher, and NASA engineer John traveled to Argentina in a bid to climb the mountain alongside a team of other keen explorers, many of whom were part of the Mazamas climbing club.

The team set off on January 19, 1973, and they successfully went on to make it to Camp 3 - which was over 19,000 feet high.

They continued their travels the next day, but one member of the party became unwell so he and another went back to camp.

Around 3,500 climbers attempt to go up Mount Aconcagua each year (Christopher Pillitz/Getty Images)

Janet and John were some of the last people standing on the expedition, and they managed to travel a further 2,000 feet before setting up camp once more.

How did Janet Johnson and John Cooper die?

John went on to decide that he couldn't make it to the summit, and proceeded to make his way back down the mountain to Camp 3.

But he never made it and the engineer sadly died on the glacier.

Janet's untimely passing followed shortly after.

The remaining explorers made it to the summit and in interviews conducted after John and Janet's deaths, they claimed that it was dark when they got there and turned round to find Janet wasn't there.

They went on to find her 100 feet away from the snow trail and while she just wanted to 'lay [there] and die', one man roped himself to her to help Janet.

Eventually Janet's hands went on to become 'black and swollen', likely from frostbite caused by the mountain's below-freezing temperatures.

After much difficulty, they safely made it back to Camp 3 and stayed the night. But the next morning, Janet was nowhere to be seen.

Explorers set up camps on route to the summit (Rafa Samano/Cover/Getty Images)

They went down without her and her body wasn't found on the glacier until two years later.

Questions of foul play

Both Janet and John's deaths went on to be ruled as accidental and it was presumed that they both fell and fell victim to the elements, but there has long been questions of if foul play was involved.

“There is sufficient mystery and enough unanswered questions surrounding the death of Janet Johnson and NASA engineer John Cooper on the same 1973 expedition to have raised the suspicion of foul play,” William Montalbano wrote in a 1976 article for the Miami Herald.

New evidence uncovered

The mystery is still yet to be solved, and in 2020 - with the help of global warming - Janet's camera was unearthed from the snow.

Ulises Corvalan was part of the expedition that found her camera that had 24 photographs on it, which have helped piece together the timeline of her death.

One of the photos on the roll is Janet with John and fellow explorer Arnold McMillen.

One of the last photos of Janet Johnson and John Cooper (John Shelton)

Corvalan is an experienced guide and has analyzed Janet's photographs. He has one key question - why were Janet and John's bodies intact if they'd suffered a fall?

"[Corvalan] has seen bodies ravaged by even short falls. Bones are broken. Clothing and equipment are shredded," wrote The New York Times.

"Why, Corvalan wondered, did so little of that appear to have happened to Johnson and Cooper? Why was the damage confined mostly to their faces?"

He told the publication the long fall that was said to have killed them was 'improbable, maybe impossible' thanks to the shallow slops and uncharacteristically soft snow.

The mystery continues.