What About the Sunset?

What about the sunrise/sunset?

We get this question a lot in Flat Earth. To understand the answer, throw away all notions of a huge blazing gas ball sun, central to our system.

The sun is a small, mobile, local light. It makes a circuit across the sky every day. When it goes too far away, it disappears into the line of convergence, or horizon.

The best illustration I’ve seen so far is from @VerumBellator1 :

Properly understood, the sun doesn’t “set” or “rise.” It advances and retreats. No spinning globe required.

One more illustration that kinda helps too:

The sun doesn’t disappear or a curve, it merely moves beyond our line of sight.

Thanks for reading! If you have a better way of explaining sun advance/retreat, please leave your idea in the comments!

2 Comments

  1. I can see certains errors in the coin example:
    1. We can’t see the surface of the table. This is important, very important. It’s clear that if the camera is under the table surface level, the coin will disapear.
    2. The model should be in scale. The coin should be 1.4 meters (aprox) above the surface of the table. The sun is not touching the surface of the Earth, it is at 4828.032 km (3000 miles) above the surface of the Earth (According to Flat Earth Society: https://www.theflatearthsociety.org/tiki/tiki-index.php?page=The+Sun).
    If you do the same coin experiment with the correct measurements, the results will be very different.
    If you “can see” a boat below the horizon with a very powerful zoom, why you can’t never be able to see the sun at night with an extreme zoom?

  2. Hyperkubo has a very good point. The coin in the image was literally touching the table. The idea that the sun actually gets to the ground went away with the Greeks.

    Stacy, try drawing a to-scale side view with the observer on the ground, the small and local sun above the ground some distance away. Use whatever distances you prefer for the distance from the observer to the point on the ground under the sun and your own distance for the height of the sun.

    This forms a right triangle. You know the distance over the ground, then a right angle, then the height of the sun. You can solve this triangle using Side-Angle-Side. The angle where the observer is tells us the expected angular elevation above the horizon the sun would appear over flat earth.

    I calculated Side-Angle-Side myself, but there are online calculators to make it faster. For example, on the page linked here it’s calculator #2.
    http://www.analyzemath.com/Geometry_calculators/right_triangle_calculator.html

    The Orthographic view with the sun and the boat isn’t to scale, it’s not meant to be or it would be very boring. The lines to the “blind spot”, or commonly called the “vanishing point”, when drawn to scale should not be straight lines, they should be curved, flattening out in the distance. Never touching, and certainly not crossing. I’ve seen similar images before and they are quite misleading as they suggest that the distant objects somehow continue in that same straight line past the vanishing point.

Leave a Reply