Are the rays real?

During the 2001 total solar eclipse in Zambia I saw two sets of rays. One set of rays was actually present around the sun, the second set were not.

To o and Notice

The first rays, shown in the top photo, spread out from the diamond ring, the last bit of the solar photosphere visible before the moon totally obscures the sun. These rays were straight lines extending on both sides of the diamond ring. They were visible by eye as well as in the photograph, however the rays that were visible by eye did not have the same pattern as those in the photograph.


rays from the diamond ring
Rays spread out from the diamond ring.

The second set of rays were long thin rays that spread out from the corona. These rays were visible by eye and in some photographs, but not in this photograph. The rays stretched out radially from the center of the sun and did not continue on the other side of the sun. The lines seen by eye and those that show in photographs did have the same pattern.

the corona also had rays
Long thin rays also spread out from the corona,
they are not visible in this image.

What's Going On?

The rays spreading out from the diamond ring were not real, while those from the corona were real.

The symmetry of the rays in the diamond ring comes from diffraction. A bright point of light will make diffraction rays when it passes through the flat sided blades of the camera iris. The top photo tells me that the camera iris had 6 blades. The lines in the eye came from imperfections in the cornea of the eye. These linear imperfections also diffract the light, but of course they do not have the same pattern as those produced by the camera.

The long thin lines radiating out from the outer corona were actually there. They show the same pattern by eye and in all photographs with long enough exposure.

Go to In the Dark

Scientific Explorations with Paul Doherty


1 July 2001