Every once in a while, someone with far more self-confidence than is warranted will travel to the “end” of the Earth in order to “prove” that we live not on a flattened sphere, but on a pancake.
They traveled to Antarctica for a “final experiment” and attempted to sail to the edge, always ending up disappointingly realizing that the Earth is round, or at least admitting that their own models of a flat Earth are somewhat lacking. But they don’t need to. As an Internet hero recently demonstrated, you can personally prove that the Earth is round without leaving it and with very basic equipment.
In a time-lapse purportedly filmed between March 2024 and March 2025 and posted to Reddit, you can see a piece of evidence traced on the ground.
By following the shadow corner of the garage and marking where it is at the same time of day over the course of a year, you can see that it draws a sort of figure eight symbol, known as an analemma. Analemmas are created by the relative motion of the Earth and the Sun and are very well described by the usual models of the solar system in which the Earth – an oblate spheroid – orbits the Sun.
If the Earth were a flat surface and the Sun moved above us and you traced shadows over the course of a year, the tip of the shadow would remain stationary. Instead, you get these numbers, which require a bit of orbital and calendar knowledge, but are far more interesting than anything a flat Earth model can produce.
The simple answer to why they occur is that the Earth’s tilt of 23.5° makes the Sun appear higher or lower in our sky throughout the year (affecting the vertical axis) while the Sun’s elliptical orbit affects the horizontal position.
“The Sun will appear at its highest point in the sky, and at the highest point in the analemma, in summer. In winter, the Sun is at its lowest point,” explains the Stanford Solar Center. “Intermediate times generate the rest of the analemma model. Analemmas seen at different Earth latitudes have slightly different shapes, as do analemmas created at different times of day.”
But while the planet’s orbit and tilt play a role, it’s not the only factor involved. In fact, what analemmas actually measure is how much local time (e.g. UCT) differs from mean solar time as the Earth makes its way around the Sun.
“Introductory textbooks and other educational sources sometimes explain the horizontal displacement of the analemma as resulting solely or primarily from the eccentricity of Earth’s orbit,” explains an article on the subject.
“This is clearly incorrect: Kepler’s second law implies that the orbital angular velocity of a planet is faster than average when the planet is near perihelion and slower when it is near aphelion. If this were the dominant factor in determining the equation of time, then the azimuth of the Sun, observed at noon, would be greater than 180◦ for half the year and less than 180◦ for the other half, which would give a number zero rather than a number eight for the analemma,” he continues.
“Orbital eccentricity plays an important role in determining the precise form of the equation of time, but the analemma would still be an eight if Earth’s orbit were perfectly circular.”
The reason for the number eight analemma is the difference between the Sun’s actual position in the sky and the mean solar time measured by your own clock.
“The apparent variation in the position of the Sun has been studied intensively by astronomers and is well understood. It is the cause of variations in the length of a solar day and of the difference between solar time and mean time,” explains another article on the subject.
“The variations are summarized in an expression called the equation of time (the term ‘equation’ is used here in a historical sense, meaning a correction or adjustment).”
For example, 12 o’clock is noon every day of the year, according to our clocks. But solar noon, when the Sun is actually highest in the sky, varies throughout the year. Take a photo of the Sun at noon every day and you map the difference between the time measured on your watch and the Sun’s actual position at that time, a result of the Earth’s tilt relative to the Sun at that time of year.
On Earth, depending on where you are, the analemma can appear at different angles, although it always traces this figure-eight pattern. The angle of the analemma at different latitudes is predicted by a spheroid Earth model, but in a flat Earth model you have to invoke the Sun moving in strange trajectories, and without regard to physical laws, in order to reproduce this effect.
In some “ideas”, the Sun rises and falls to account for the seasons, but for some reason without a corresponding size change in the sky. None of these accounts for the analemmas as well as current models, nor for the different analemmas observed at different altitudes.
“I’m a physics student. This is just another piece of evidence that fits our models of the solar system,” Reddit user Haventyouheard3 added in response to the video. “It is, however, impossible to object to the use of a flat Earth model, because even they do not know what is happening in their model.”
