You don't need to build a rocket to prove the Earth isn't flat – here's the simple science

November 27, 2017 by Ian Whittaker, The Conversation
Credit: Shutterstock

Could 2,000 years of belief be wrong? Are we in fact living on a disc rather than a globe? One believer from the Flat Earth Society is determined to find out. "Mad" Mike Hughes is all set to build his own rocket to see for himself that the Earth is flat.

For the last 50 years, we've been able to view pictures of the Earth from space, which might seem like all the proof you need to see that our planet is in fact round. But the awareness of how easily images can be doctored and the growth of internet conspiracy theories appears to have fuelled a resurgence of belief in a flat Earth.

At the same time, there's a lack of understanding of the science that has long been used to demonstrate that we live on a globe, without the need to leave it. I wish Hughes well with his endeavour, as he has at least been willing to try and prove his theory. Perhaps if more people really could see for themselves the evidence, we might be able to reverse this worrying trend. A good place to start would be by making sure children have the chance to try out simple experiments in school.

One of the best documented methods for determining the Earth's roundness was first performed (to our knowledge) by the ancient Greeks. This was achieved by comparing the shadows of sticks in different locations. When the sun was directly overhead in one place, the stick there cast no shadow. At the same time in a city around 500 miles north, the stick there did cast a shadow.

Cast no shadow. Credit: Shutterstock

If the Earth were flat then both sticks should show the same shadow (or lack of) because they would be positioned at the same angle towards the sun. The ancient Greeks found the shadows were different because the Earth was curved and so the sticks were at different angles. They then used the difference in these angles to calculate the circumference of the Earth. They managed to get it to within 10% of the true value – not bad for around 250 BC.

Another piece of evidence for a globe is the difference between the night skies in the northern and southern hemispheres. The view is completely different because the Earth beneath you is pointing in a different direction. If the Earth were flat, the view should be the same. This can be made even easier by simply comparing when it is night and day in each country.

You can observe the planets as well. They all rotate, and watching over the course of a few days gives a clear picture they are spherical rather than flat. The chance that most of the planets are spherical but the Earth is flat seems very unlikely.

Fake science

But when science experiments are performed incorrectly they can appear to give the opposite result. If they are shared through social media, these false ideas can be spread quickly with no one to point out their flaws. One common example is the Bedford Level experiment, a form of which was first carried out in 1838 and used to "prove" the Earth was flat for over 30 years before an explanation was found.

This experiment involved placing a marker at a set height at either end of a canal about six miles long. If the Earth is round, then one marker should appear lower than the other when viewed at the same time through a telescope because the furthest marker would have fallen away with the curvature of the Earth. But it was reported that the markers are the same height, suggesting the Earth is actually flat. Modern day Flat Earth theorists still quote this experiment.

The problem is this doesn't take into account the optical effect of the air over the intervening water, which bends or "refracts" the light as it travels from the marker to the telescope and makes it look like they are the same height. The solution is to use multiple markers along the length of the canal which, when observed, all appear to be at different heights.

Perhaps the most impressive experiment that even schools can do today is to send a camera up in a high-altitude balloon. The footage will show that from a high-enough vantage point you can see the curvature of the Earth. This is what Mike Hughes will find if he ever makes his rocket work.

Ultimately, arguing on the internet is not the best way forward for any scientific endeavour. We need to provide the means for people to test these theories themselves and to understand the results they get.

Explore further: Image: Earth as viewed from 10,000 miles

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dsylvan
5 / 5 (1) Nov 27, 2017
Rocket rides are way too expensive and risky. A vacation will do. If you can get to a place by the coast and a hundred meters or so above sea level with an unobstructed view of the horizon, say on a deck with a long straight and level railing, visually line the railing up with the horizon on both ends, and the horizon straight ahead will be above the railing. That's the curvature of the Earth. (The ocean isn't domed shaped all by itself)
eljo
5 / 5 (2) Nov 27, 2017
"If the Earth were flat then both sticks should show the same shadow (or lack of) because they would be positioned at the same angle towards the sun."

Just saying... a flat earther would not assume that the sun is far away. A sun that is close to the flat disk could create the same shadows (the old pendulum idea). So... you first have to prove to a flat earther that the sun is at a large distance.
And with regards to refraction: refraction doesn't care whether a surface is concave or convex (which also is a thing ) , so that would still require a proof for an earlier underlying assumption (that it is spherical).
This whole flat Earth business is actually a good exercise for science writers in dismantling their own basic assumptions. It is a warning that simple things are not simple and forces one to think even harder. So...how can one prove that the sun is far away? How can one prove that the earth is spherical? Hint. to convince them you must only use pre-18th century phys.
cantdrive85
1 / 5 (6) Nov 27, 2017
There is another group who believe another fake science which ignores blatant scientific evidence, similar to that of the flat earthers and epicyclists. They can be called the 'Acolytes of the Gravity Only Society' and Einstein is their God. In order to save their religion they had to invent 75% more invisible and magical God dust to keep their Universe coherent. They invented scawry invisible superstupendous black hole monsters and superspinny lighthouse stars all formulated with fake science equations and false entities such as singularities and infinite densities of gravitational morontitude.
It would be amusing if they weren't wasting huge amounts of resources and progress in search for their holy ghosts and dieties. The Gravity Only Society will be laughed at just as they mock the flat-earthers.
adam_russell_9615
5 / 5 (2) Nov 27, 2017
If the earth were flat there would be no time zones.
Otoh, gotta give him credit for designing and building his own rocket, and then putting his life on the line. That takes balls.
Whydening Gyre
5 / 5 (4) Nov 27, 2017
There is another group who believe another fake science which ignores blatant scientific evidence, similar to that of the flat earthers and epicyclists. They can be called the 'Acolytes of the Gravity Only Society' and Einstein is their God. In order to save their religion they had to invent 75% more invisible and magical God dust to keep their Universe coherent. They invented scawry invisible superstupendous black hole monsters and superspinny lighthouse stars all formulated with fake science equations and false entities such as singularities and infinite densities of gravitational morontitude.
It would be amusing if they weren't wasting huge amounts of resources and progress in search for their holy ghosts and dieties. The Gravity Only Society will be laughed at just as they mock the flat-earthers.

CD,
There is no "Gravity Only Society".
It's the "Gravity First at A Macro Scale Society"...
Whydening Gyre
5 / 5 (2) Nov 27, 2017
If the earth were flat there would be no time zones.
Otoh, gotta give him credit for designing and building his own rocket, and then putting his life on the line. That takes balls.

Adam,
This guy knows Earth ain't flat. And he was never gonna ride that rocket. Just an attention whore...
eljo
not rated yet Nov 27, 2017
If the earth were flat there would be no time zones.
True. But in their schematics that also works on a flat disk with a sun hanging from a pendulum. You have to build it up from the beginning of science. How is it that a medieval, pre-medieval, and ancient man could assume that the sun is far away?
JohorSC
1 / 5 (2) Nov 28, 2017
The camera experiment has also some flaws. The lenses of todays mobile phones or cameras are usually designed to picture the ego of us. As our ego is very huge they have to picture a wide range and by doing so there are distortions in the photos (also referred as 'fisheye'). Even flat lines appear to be spherical...
antialias_physorg
5 / 5 (4) Nov 28, 2017
This guy knows Earth ain't flat. And he was never gonna ride that rocket. Just an attention whore...

Yeah...he was already building the rocket before he 'converted' to the flat Earthers (he had a Kickstarter page going that wasn't bringing in any money. So he 'converted' to something where he knew there would be plenty of gullible idiots...and lo-and-behold: they gave him money.)

Note also that the guy has flown a rocket before - which lead to him being seriously injured. So he already has the 'evidence' of anything he's purporting to 'prove'
Eikka
not rated yet Nov 28, 2017
So... you first have to prove to a flat earther that the sun is at a large distance.


Parallax.

The distance of the earth to the sun can be measured easily by comparing the angle of the sun seen from two different vantage points at the same time of day when the sun is low to the horizon, so that the curvature of lack of curvature of the earth won't mess up with the measurement.

Two points a mile away would suffice. Now the problem is that the flat earther will refuse to run the numbers through.

The fundamental problem isn't ignorance of facts, but the fact that a psychotic person convinced of the (un)reality of something real is suffering from cognitive distortions in their very thinking process, and so will continue making strange associations and interpretations of reality despite what you tell them. It's like a broken calculator that reads 1+2 = 4

CubicAdjunct747
not rated yet Nov 28, 2017
Hope this guy crashes and dies in his rocket. Another way to prove earth is round is lake michigan. If you go on the east side of the lake on the shores of Michigan and look west, you can see just the tops of the skyscrapers of chicago above the waterline/horizon with simple binoculars.
cantdrive85
2.2 / 5 (6) Nov 28, 2017
This guy knows Earth ain't flat. And he was never gonna ride that rocket. Just an attention whore...

Yeah...he was already building the rocket before he 'converted' to the flat Earthers (he had a Kickstarter page going that wasn't bringing in any money. So he 'converted' to something where he knew there would be plenty of gullible idiots...and lo-and-behold: they gave him money.)

Note also that the guy has flown a rocket before - which lead to him being seriously injured. So he already has the 'evidence' of anything he's purporting to 'prove'

Just think, if he announced he was looking for dark matter he would have had billions thrown at him with zero expectations of success. He picked the wrong fake science.
Eikka
3.8 / 5 (4) Nov 28, 2017

Just think, if he announced he was looking for dark matter he would have had billions thrown at him with zero expectations of success. He picked the wrong fake science.


Why don't you prove that assertion and try it yourself? If you can get funding just by that, you can write a paper about it and reveal the whole show - a Sokal affair in astrophysics would produce red faces all around.

Of course you won't, because you don't want the possibility of proving yourself wrong.
TheGhostofOtto1923
2.5 / 5 (2) Nov 28, 2017
"If the Earth were flat then both sticks should show the same shadow"

- Yeah well maybe it's a convex saucer yes? No? Similar to benfords 'Bowl of Heaven" but with a singularity instead of a star, for gravity, and humans living on the outside.
http://www.gregor...blished/

Neil degrasse Tyson had a nice rebuttal
https://www.inver...nspiracy

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