The Pink Floyd Experiment

Now, let's talk about the night sky.

What Flat Earth Models Predict

Every flat Earth model, regardless of its specific details, requires celestial objects to be relatively nearby – typically on or attached to some kind of dome or "firmament" above a flat plane. This isn't optional; it's required by the geometry of their model. If stars were truly distant (light-years away), the various observations we make wouldn't work on a flat Earth. You can check challenge number 1, where we conclude that a flat Earth requires a local sky.

So, according to flat Earth theory, when stars appear to rotate across the night sky, they're actually attached to or projected onto a local rotating dome, probably a few thousand kilometers above Earth's surface.

Here's where the turntable analogy becomes devastating: if stars are on a nearby rotating dome, then almost everyone on Earth is positioned off-axis from that rotation. Just like standing to the side of a spinning record player, observers away from the supposed rotation center should see elliptical star trails, not circular ones.

In fact, on a flat Earth with a dome centered over the North Pole, someone standing in, say, Sweden (where I am) would be roughly 3,000 kilometers off-axis. Someone at Earth's equator would be about 10,000 kilometers from the pole. If the dome is at an altitude of 5,000 kilometers (a generous estimate for flat Earth models), the geometry is brutal: observers would be offset from the rotation axis by distances comparable to or greater than the dome's height.

This would produce massively elliptical star trails – not slightly oval, but severely distorted, with the long axis of the ellipse roughly twice the length of the short axis. For someone at the equator viewing a 5,000 km high dome, the distortion would be even more extreme.

What We Actually Observe

But here's the thing: star trail photographs always show perfectly circular trails. Always.

From every location. Without exception.

You don't need to take my word for it. Go outside on a clear night with a camera, point it at the northern sky (if you're in the northern hemisphere), set a long exposure, and come back in a few hours. You'll capture beautiful concentric circles of star trails centered on Polaris, the North Star.

Those circles will be perfect. Not elliptical. Not oval. Circular.

And here's what makes this evidence so powerful: everyone sees circular trails from their location. People in Norway see circles. People in Egypt see circles. People in Singapore see circles. People in South Africa see circles (though they see different stars circling a different point – more on that in a moment).

If Earth were flat with a local rotating sky, this would be geometrically impossible. The vast majority of observers would necessarily be off-axis and would see elliptical trails. Only the lucky few standing directly under the rotation axis – supposedly at the North Pole – would seecircular trails.

But we all see circles.

The Hemisphere Problem

It gets worse for flat Earth models. Much worse.

In the northern hemisphere, we see stars rotating around the north celestial pole (near Polaris). In the southern hemisphere, observers see stars rotating around the south celestial pole (near Sigma Octantis). And both hemispheres see perfectly circular trails around their respective poles.

Think about what this means: you can't have two rotation centers on a single dome. A dome can only rotate around one axis. Yet observers in the north and south simultaneously see circular rotations around opposite points in the sky.

On a flat Earth, this is impossible. You'd need two separate domes rotating in opposite directions, which creates a whole new set of impossible problems. How do they not interfere with each other? Where do they meet? How do observers in intermediate locations see both sets of stars?

On a spherical Earth, this makes perfect sense: different observers are looking outward from different positions on the globe, so "up" points in different directions. Someone in Australia is oriented differently than someone in Sweden, so they're looking at a different part of the sky when they look "up." The celestial sphere appears to rotate around different axes because the observers themselves are oriented differently.

The Latitude Connection

Here's another nail in the coffin: the altitude of the celestial pole above your horizon exactly equals your latitude.If you're at 60°N latitude (like Stockholm), Polaris appears 60° above the northern horizon. At 30°N (like Cairo), it appears 30° above the horizon. At the equator (0° latitude), the celestial poles sit right on the horizon. At the South Pole (90°S), the south celestial pole is directly overhead.

This relationship – pole altitude equals latitude – is exactly what you'd expect on a rotating sphere where your "up" direction changes based on where you are on the globe. It's what the spherical Earth model predicts.

But on a flat Earth? There's no mechanism for this. Everyone's "up" points in the same direction (perpendicular to the flat plane), so why would the apparent position of the rotation axis change systematically with your position? Flat Earthers have no coherent explanation for this observation.

You Can Check This Yourself

This is what makes star trails such a powerful piece of evidence: it's directly verifiable by anyone. You don't need expensive equipment. You don't need to trust NASA or any other authority. You just need:

• A camera (even a smartphone with long-exposure capability)

• A tripod or stable surface

• A clear night sky

• A few hours of patience

Point your camera north (or south if you're in the southern hemisphere), set it for a long exposure or multiple stacked exposures, and see for yourself. The circles will be there.

Better yet, coordinate with someone far away from you – ideally on a different continent. Take star trail photos at the same time. You'll both capture circular trails, despite being thousands of kilometers apart and supposedly at very different distances from the "rotation axis" if Earth were flat.

Why This Matters

In an age where misinformation spreads rapidly, it's valuable to have simple, verifiable evidence that anyone can check. Star trails are exactly that. You don't need to understand complex physics or trust institutional authorities. You just need to look up.

The geometry is straightforward: off-axis rotation produces ellipses, not circles. We observe circles from all locations. Therefore, we're not observing a local rotating dome.

The conclusion is inescapable: Earth is approximately spherical (actually an oblate spheroid – slightly flattened at the poles – but that's a detail for another time), and it rotates on its axis beneath a sky of extremely distant stars. This is why all observers see circular star trails appropriate to their location on the globe.

The Pink Floyd Connection

I posted about this recently on social media using a photo of a Pink Floyd record on a turntable. It seemed fitting – Pink Floyd's music has always been about perception, reality, and seeing through illusions. "Wish You Were Here" felt particularly appropriate for a discussion about looking up at the stars and understanding what they tell us about where we are.

The analogy holds: just as you can't make an off-center dot on a spinning record trace a circle when you're viewing from the side, you can't make stars on a nearby rotating dome trace circles when you're positioned off-axis from that dome's rotation.

The evidence is literally written in the stars. We just have to look up and pay attention.

Going Deeper

If you're interested in the rigorous mathematical proof that star trails are incompatible with flat-Earth geometry, I've written one that uses vector algebra and differential geometry. It addresses every possible variant of flat Earth cosmology – local domes, non-rigid rotation, holographic projections, you name it. The conclusion is the same: the observed patterns of circular star trails can only occur on a rotating spherical Earth with distant stars.

But you don't need to understand maths to grasp the core insight. The turntable test tells you everything you need to know: circles aren't ellipses, and what we observe in the sky can only happen if Earth is round.

Your Turn

Next clear night, go outside. Look up. If you have a camera, capture some star trails. If not, just watch the stars slowly wheel across the sky over the course of an evening. Polaris (if you're in the northern hemisphere) will barely move, while stars further from it will trace larger circles.

Those perfect circles are telling you something fundamental about the shape of the world beneath your feet.

Listen to them.