Story behind one of the 'most terrifying photos' ever taken in space is chilling

The astronaut behind one of the 'most terrifying photos' ever taken in space explained why it was it was chilling.

The late Bruce McCandless II opened up about his history-making expedition before his death, which included snapping a particularly haunting pic.

The idea of space is scary for most of us, not least of all for the fact it's as far away from our home planet as possible without factoring in 'space junk' or potential alien megastructures and the weird blobs growing outside the International Space Station.

However, possibly the most terrifying thing to happen in space has actually been captured on camera.

In 1984, the then-47-year-old aviator embarked on a Space Shuttle mission to deploy two communication satellites for the first time.

And it wasn't the only major NASA first, as the Boston-born man found himself the subject of the 'most terrifying space photo' ever taken at the time as he made the first untethered 'spacewalk'.

McCandless and fellow astronaut Bob Stewart had strapped themselves into Manned Manoeuvring Units (MMUs) and left the comfort of their ship.

The MMUs allowed them to move around in open space, untethered from the spacecraft at around 28,900 kilometers per hour.

This meant McCandless was 'space walking' for almost seven hours.

The iconic image from the Challenger shuttle shows McCandless floating freely above Earth, which is frightening even if you don't suffer from astrophobia.

NASA said the picture was the 'most terrifying space photo' (NASA)

More than three decades after becoming the first human in history to complete an untethered free flight, McCandless told The Guardian there were been tensions in NASA about the plans.

"My wife was at mission control, and there was quite a bit of apprehension,” he explained.

He also said it didn't feel as scary as it looked, adding: "I wanted to say something similar to Neil [Armstrong] when he landed on the Moon, so I said, 'It may have been a small step for Neil, but it’s a heck of a big leap for me.' That loosened the tension a bit."

McCandless also said while he had been told about the silent vacuum of space, his tranquility was interrupted.

The astronaut was walking for almost seven hours (NASA/MMU)

He joked that multiple people on his radio were asking a myriad of questions, which meant things weren't exactly peaceful.

He continued: "My walk lasted six hours 45 minutes, and I stayed alongside the shuttle the whole time, moving 100 yards one way, 100 yards back.

“I was travelling at more than 18,000 miles an hour, but wasn’t aware of it, because the shuttle was going at the same speed.

“It was only when I looked at the Earth that I could tell we were moving fairly rapidly.”

At one point, he careered over the Florida peninsula and said it was 'reassuring' to see something he recognized below.

"It was a wonderful feeling, a mix of personal elation and professional pride: it had taken many years to get to that point.”

After logging more than 312 hours in space, he retired from NASA in 1990 and went on to work for the Lockheed Martin Space Systems.

At the age of 80, McCandless died in 2017 and was buried at the United States Naval Academy Cemetery in Annapolis.