
One of the first lessons we learn in school is that the Earth is a globe that rotates on its axis and orbits the sun.

But there is an ever-growing community of people who reject 'globehead' thinking and insist that the world is, in fact, flat.

These 'Flat Earthers' believe that our planet is encircled by a giant, heavily-policed ice wall and that gravity is just an unproven theory.

They also claim that NASA is a fraudulent organisation and that all the photographs and video footage we have from space are computer-generated imagery (CGI).

The crazy - and scientifically disproven theory - will be laughable to most. Humans have known the earth is round for thousands of years, while ancient Greek mathematician Eratosthenes calculated the circumference of the planet with surprising accuracy before his death in 195 BC.

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Sceptic Spencer Marks (left), debates with Flat Earther Nathan Thompson (right), who founded the movement

'Flat Earthers' believe that our planet is completely flat and gravity is no more than just an unproven theory

A pair of Flat Earthers show off T-shirts advertising their theory, which also states that our planet is encircled by a giant, heavily-policed ice wall

The curvature of the Earth is also visible to everyday people in hundreds of different ways. From the way boats can disappear over the horizon, to the observance of every other planet in our solar system - or even just the moon for that matter - or to the reason why the earth has a tropical equator and polar ice caps.

But it appears that, quite worryingly, tens of thousands of people have decided to forgo basic logic and scientific evidence in favor of conspiracy theories.

Experts believe certain people are attracted to the theory because the (false) belief they know something the rest of the world does not can make them feel superior. Some Flat Earthers also appear to show signs of paranoia, and think they are being persecuted by the government or unknown forces for their beliefs.

The movement has attracted a number of celebrity adherents in recent months, including rapper B.o.B., former reality TV star Tila Tequila and basketball legend Shaquille O'Neal.

O'Neal stunned fans when he revealed that he thought the world was flat because when he drove from coast to coast, he didn't feel himself going up hill, or down hill.

'So, listen, I drive from coast to coast, and this s*** is flat to me,' he said.

'I do not go up and down at a 360-degree angle, and all that stuff about gravity, have you looked outside Atlanta lately and seen all these buildings?

'You mean to tell me that China is under us? China is under us? It’s not. The world is flat.'

The Earth has a radius of approximately 3965 miles, which calculates to having an average curvature of around inches per mile - a difference far too small for a person to notice when spread out over a large distance like a mile.

The movement has attracted a number of celebrity adherents in recent months, including rapper B.o.B (left) and basketball legend Shaquille O'Neal (right)

Other great minds to have joined the movement including former TV reality star Tila Tequila (pictured entering Celebrity Big Brother in 2015)

Nathan Thompson, 31, a network marketer based in Orange County, California, set up the Official Flat Earth and Globe Discussion group on Facebook in June 2016.

The group now now boasts more than 42,000 members and even Nathan has been taken aback by its rapid growth.

He said: 'I actually cannot believe how popular it's becoming. It took about four months to get to 10,000 members, but in the last four months that has multiplied to more than 30,000 members.

'I woke up this morning and I have 2,200 members to approve. The group is just exploding.'

He was introduced to the notion of a flat Earth by a friend and says he initially dismissed it as a 'ridiculous idea'.

Nathan added: 'I said 'What about the pictures from space? Nasa has pictures'. He said 'Well, they are all composites'.

'I thought this was the craziest idea I had ever heard and at first I was extremely skeptical. For the first month all I wanted was for the Earth to be a globe.

Nathan Thompson, 31, a network marketer based in Orange County, California, set up the Official Flat Earth and Globe Discussion group on Facebook in June 2016

In February this year, Thompson took his Flat Earther views to the Grammys with model Madeline Monaco

Thompson reads from one of his Flat Earth texts on March 25 in Orange County, California

An example of how the Flat Earthers believe the world is laid out, taken from the Official Flat Earth & Globe Discussion Facebook page

'I thought I was going to debunk it but after a month of not sleeping and really digging through the information, I was a Flat Earther.

'The facts all point to the fact that the ball Earth is a lie. And once you go flat, you don't go back.'

He now spends his time travelling across the USA to meet other Flat Earthers and spread his message to potential new converts.

He said: 'I would say 50 per cent of the time someone leaves a conversation saying 'I didn't know any of this information and I will look into it.'

'Then the other 50 per cent of the time they just reject it regardless of what you show them.

'I would say that the average Flat Earther is someone who had already been questioning reality.'

Nathan recently went inside enemy territory when he took a group for a tour of NASA's Jet Propulsory Laboratory in Pasadena.

He also recently hit the headlines when a video of him in a coffee shop challenging a NASA employee to admit the organisation was bogus went viral online (pictured left in the NASA employee, and right is Thompson)

He also recently hit the headlines when a video of him in a coffee shop challenging a NASA employee to admit the organization was bogus went viral online.

The Flat Earth community is also united in the belief that the continent of Antarctica is actually an ice wall that stretches around the perimeter of our world.

'There is an ice wall that they have been guarding since 1961,' Nathan said.

'I have not personally been there, but I have heard people have been turned around at gunpoint for trying to investigate the ice wall independently.'

Spencer Marks, 55, an investigator with the Independent Investigations Group, a rational, scientifically-based skeptics organisation, recently met Nathan and other Flat Earthers while they were evangelizing in Orange County.

He said: 'Flat Earthers will hold on tightly to the confirming evidence and discard any contradictory evidence.

'But the way science or logical critical thought works is that you look at evidence.

'In this case, for thousands of years, we have known that the Earth is round because it's what all the evidence points to.

The Flat Earth movement now now boasts more than 42,000 members and even Nathan has been taken aback by its rapid growth (pictured are a group of Flat Earthers during a get-together in March)

Thompson (right) joins two other Flat Earthers at a meet-up on March 25 in Orange County, California. He said it took about four months to get to 10,000 members, but in the last four months that has multiplied

Thompson (left) and film Producer Fred Schneider hold up two key texts of flat earth literature - The Greatest Lie on Earth: Proof That Our World Is Not A Moving Globe by Edward Hendrie and Zetetic Astronomy: Earth Not A Globe by Samuel Rowbotham

A woman models a Flat Earth t-shirt, which quotes Bible verses on the back

'I think the Flat Earthers cling to their beliefs because it feels to them like they have special knowledge that other people are not aware of, which gives them a sense of purpose or meaning, the idea that you have discovered something that others do not have.

But despite Spencer's skepticism, nothing will convince Nathan to go back to believing in a globe world - even if he believes being such a vocal advocate for flat earth puts him in personal danger.

He said: 'I am just out here trying to wake people up. I feel like it is my purpose in life.

'I pray every day that they do not torture me. I really think I have cross-hairs on my back.

'I do not know if it is the CIA, the FBI, or whoever is protecting these people that run the world.

'We are not dealing with normal people, they are psychopaths. You have to get inside the mind.

'There is really no logical reason to lie to everyone, to say the world is flat, other than world domination, stealing money, confusing people, and that is their plan.

'I want to stay under the radar, but I don't think I can. I can't say I regret anything. The truth set me free.

'The Flat Earth community is the realest group of people you will ever come across. We all share this bond that we do not appreciate lies - we just want to look for the truth.'