In 2017
Christine dragged me on the Katy Trail near St. Louis to see the eclipse. We
were not in the totality. The first effect I noticed was the sickling. People
were making pinhole viewers with blades of grass or a circle with thumb and
forefinger. Sickling, the crescent moon shadow, was everywhere. The next was shadow bands. The sickling
turned off and shadow bands, alternations of light and dark, appeared on the
ground. They were straight and went on forever. Towards maximum darkness, and
stillness, the shadow bands clicked off and then reappeared on the other side
of the eclipse. Then the bands turned off and sickling reappeared. The shadow
bands did not move. I don’t know if their position was the same on both sides
of the eclipse.
I had not
heard of shadow bands before. Shadow bands are an interference pattern. An
interference pattern occurs when a light is split, and the two slits create a
wave interference pattern. The question is where the interference comes from.
One slit is obvious, even if curved, the eclipse of the sun. Some think the
second slit is an atmospheric effect. Another possibility is a quantum effect,
sufficient light bending around the other edge of the moon. Sneer in whichever
way you like.
In 2024
Christine dragged me to the totality, Thornwood preserve near Indianapolis. I
brought a tape measure to see if I could better observe the shadow bands. There
was no sickling. Other people in the totality noticed this as well. There was
sickling everywhere else. It was as though there was too much light. I didn’t
see shadow bands. Fortunately, Speedway sold us eclipse glasses. I saw the
pearls where the light peeps around the moon’s mountains. When it was too dark
to see through the glasses, I looked at the totality and saw the flare near the
bottom. I didn’t see a quantum dot at the center.
Rather than quantum, is the moons gravity sufficient to bend enough light at an angle? Other observers see flickering and motion. Once the pattern appears, the flickering sounds atmospheric.
Neither quantum nor gravity is sufficient. When the light strikes earth's atmosphere at an angle, it splits. At a subsequent atmosphere layer, it splits again, that light interferes the original beam causing the pattern.
A systemic
error is that everyone is looking up and doesn’t see the other effects. Another
is that the cool kids with the equipment head for the totality.
