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A corona from pollen dust imaged by Eva Seidenfaden ~ "Paraselene" atmospheric optics site ~ at Trier, Germany May 12th '08.
©Eva Seidenfaden, shown with permission.

Water drops are not essential to make a corona, the bright aureole and rings we see around the moon or (when its bright disk is well shielded) the sun. Pollen, coal or telescopes will do equally.

Light waves scattered from the outsides of small particles combine in a diffraction pattern to make a corona. Therefore the particles can be opaque.

Pollen grains shed in billions by spring trees produce excellent coronae. Grains from a single tree variety are same-sized and hence their coronae are sharp and multi-ringed. The grains have air sacs to help disperse them and these orient each grain. The result is anisotropic scattering and oval rings with bright areas.

Telescopes? Babinet's Principle predicts that an aperture of the same shape as an obstruction produces the same diffraction pattern. The tiny star Airy disks seen under high magnification are in-effect corona produced by the circular telescope aperture.