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A Hathor halo?

A solar phenomenon could have inspired ancient Egyptians.
OMearaStephen

An uncommon solar halo display for subtropical latitudes occurred over Maun, Botswana, last February. It’s called a circumscribed halo, and the sight of it brought to mind another type of halo that may adorn some hieroglyphs in ancient Egypt.

Searching for solar halo phenomena requires not only some knowledge of clouds (and sunglasses to cut down on glare) but also a habit of looking up more than down as the day progresses, as some phenomena can be fleeting. Here in Botswana, occurrences of the 22° solar halo and its associated ice-crystal phenomena — induced by interactions with rays of sunlight — are common during the country’s wet season. That’s when veils of ice-crystal-laden cirrostratus clouds (the type that usually produces the halo phenomenon) often precede or follow passing thunderstorms.

ASYOM0718_02
The February sighting began with an enhancement of the top of the 22° halo that grew into the upper tangential arc — an ice-crystal display that curves outward from the top of the halo, like the horns of a bull. As the Sun rose, the horns began dropping down alongside the halo. Meanwhile, the same phenomenon began in reverse from the bottom of the 22° halo, until the horns merged into the circumscribed bow. You can see these features in the picture to the right.

Like the 22° halo, a circumscribed halo is created when light passes through hexagonal pencil (or column) crystals. The difference is that the crystals that form the 22° halo twirl around three axes, whereas the crystals that create the circumscribed halo float horizontally rotating around two. As described earlier, a circumscribed halo forms from the union of the upper and lower tangential arcs and is visible when the Sun lies between 35° and 55° above the horizon. The image here shows its appearance midway up the sky.

ASYOM0718_01copy
Occasionally, the 22° halo (the inner circle) coincides with the sighting of a circumscribed halo. Both phenomena are caused by sunlight passing through ice crystals in the upper atmosphere.
Stephen James O’Meara
Symbols in the sky?
As I admired the warped-looking ice-crystal complex, including the orange interiors of the rings and the fuzzy bluish exteriors, my mind was drawn to a photo I recently shot while taking in the ancient Egypt exhibit at the Ashmolean Museum in Oxford, England. One depiction in particular caught my attention: the winged goddess Hathor, with her telltale cow horns set in a solar disk atop her head.

In ancient Egypt, the hieroglyph for the Sun is a circle surrounded by a ring, which some scholars have interpreted as a 22° solar halo. Certainly the ancients had also seen circumscribed halos and more. The horns of Hathor are particularly interesting. They represent the Apis, a bull revered in ancient Egypt as a fertility god. The bull was also associated with the solar cult and was often represented with the Sun disk between his horns.

ASYOM0718_03copy

This ornament shows one of the Uraeus cobras. The round disk represents the Sun.

Wikimedia Commons
Isn’t it possible, then, that the horns of Hathor were inspired by the hornlike appendages of a tangential arc — especially since the halos can appear at times when fertilizing rains are either approaching or receding?

Now consider the following eyelike appearance: the pupil of the Sun surrounded by the iris of the 22° halo and the lids of the circumscribed halo. The Eye of Ra, in fact, sometimes functioned as the goddess Hathor, and her Sun disk is often represented as an eye from which the Sun is born. One hieroglyph of the Sun incorporates two Uraeus cobras coiled around the disk of the Sun, looking like lobed appendages, similar to the appearance of the circumscribed halo. Food for thought?

As always, send your thoughts (and observations) to sjomeara31@gmail.com.

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