An ancient civilization on Mars was wiped out by was wiped out by a nuclear attack from another alien race.

It might sound like the plot of a science fiction novel, but Harvard scientist Dr John Brandenburg believes this catastrophic event really happened.

According to his bizarre theory, Dr Brandenburg says ancient Martians known as Cydonians and Utopians were massacred in the attack - and evidence of the genocide can still be seen today. 

Back in 2011 the scientist first postulated that the red color on Mars could have been due to a naturally occurring thermonuclear explosion, claiming chemical elements in the Red Planet's surface matched those around nuclear test sites on Earth.

Mainstream scientists have argued there is no credible physical evidence, such as a crater or fallout signatures, which points to an artificial or sudden nuclear explosion, and have highlighted that the paper was published in a relatively low level scientific journal.

But now, the theory is gaining fresh attention. 

On the Danny Jones Podcast, which has over one million subscribers, guest Jason Reza Jorjani, a philosophy PhD and science fiction writer, re-shared Dr Brandenburg's study, calling it 'alarming evidence' that life once existed on Mars.

'Every planet has a certain amount of isotopes of different materials on it, and apparently the isotopic ratio of Xenon 129 is consistent across the entire solar system, except for on Mars,' he said.

Dr Brandenburg's research centers around the 'high concentration' of Xenon-129 in the Martian atmosphere, and uranium and thorium on the surface. 

Xenon 129 is a stable, non-radioactive gas that is one of the natural forms of the element xenon, a colorless, odorless, and tasteless gas found in trace amounts in the Earth's atmosphere.

While found naturally, Xenon 129 is also released during nuclear fusion.

NASA has detected higher-than-expected levels of the isotopes Xenon-126 on Mars' Cydonia region.

The region in the planet's northern hemisphere is famous for 'apparent manmade megalithic structures,' according to Jorjani, which conspiracy theorists believe includes one that looks like a face and others as giant pyramids.

NASA scientists have stated it's an optical illusion caused by shadows and surface morphology. 

And the space agency said the chemical elements 'could have been released into the atmosphere by impacts on the surface and by gas escaping from the rocky material, which is the soil and broken rocks of the surface.' 

But Dr Brandenburg believes they are the remnants of nuclear explosions on the surface. 

'When a thermonuclear bomb is detonated, it leaves a trace of Xenon 129 in that area, which is not the normal,' Jorjani told Jones, adding Dr Brandenburg's findings were 'alarming evidence' of life on Mars. 

'And according to Dr Brandenburg, it's a very distinct signature. It's unmistakable, and it's specifically associated with thermonuclear weapons detonation.'

The 'not the normal' means higher-than-expected levels were found. 

Dr Brandenburg also argued that Mars once had an Earth-like climate home to animal and plant life, and any intelligent life would have been about as advanced as the ancient Egyptians on Earth.

The philosopher added that Dr Brandenburg's findings aligned with a CIA report that detailed how an ancient civilization once lived on Mars, but were dying because the planet had been corrupted. 

But the government agency has never confirmed there was a civilization on Mars. 

'When you put the [CIA's] data next to Brandenburg's thesis, this nuclear event took place maybe a hundred million years ago,' Reza Jorjani said.

'Joe McMonagle was tasked with remote viewing Mars in 1984. And this was a CIA operation run at the Monroe Institute. So he was working on contract for the CIA and this was done at the, at the Monroe Institute.'

The classified project was conducted at Fort Meade in Maryland, recruiting men and women who claimed to have extrasensory perception (ESP) to help uncover military and domestic intelligence secrets. AH IT'S HERE

Leading up to its closure was 'Mars Exploration May 22, 1984,' a document declassified in 2017 that has recently resurfaced online. 

McMonagle was only given the coordinates as the target and used his mind to see what was there.

'When McMonagle was doing this remote viewing session, he described being in the midst of the ruins of a megalithic city with gigantic pyramids,' said Reza Jorjani,.

'He said they, 'they seemed like they were maybe three times the size of the Great Pyramid in Giza.''

McMonagle recently shared the experience last month on the American Alchemy podcast, saying: 'I started getting an image of human beings that were trapped in a place where the atmosphere was turning bad.

'It [was] obvious these people were dying for some reason, but they were humans. They were just twice our size.'

McMoneagle obtained negatives of the Martian landscape, showing a pyramid-shaped structure on the edge of a giant impact crater where he had seen it in the CIA experiment.

He also found images of what he claimed was a human bone lying on the Martian landscape.