Sunrise Pillar
A unusually tall pillar imaged by Leslie Ginn at Stockton, California.   ©Leslie Ginn, shown with permission

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Stretching vertically an incredible 20° plus it is hard to accept that this is not some bright upwards going sun ray.

That is an illusion. Sun pillars are actually composed of untold millions of nearly horizontal going glints from tiny ice crystals.

Both plate and column aspect ice crystals can produce pillars but most are from large, wobbly and imperfect plate shapes. The low sun glints very obliquely from their undersides or from an internal reflection off their upper faces. The greater the crystal wobble from horizontal the taller is the pillar.

The pillar illusion. There is no upward light. Instead the sun is glancingly reflected by myriad crystals.