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Balloon Shadow & Glory imaged by Nigel Puttick from a hot air balloon at an altitude of 2000m over Thirsk, North Yorkshire, England.. Image ©Nigel Puttick, shown with permission.

The balloon's shadow looms uncannily onto the clouds. Surrounding the camera's position in the basket is a glory, white at its centre with successive multi-coloured rings.

Glories always surround your shadow, or at least that of your camera. Balloonists at a meet wanting to estimate drift and rate of climb often use the glory to identify which balloon shadow is theirs.
Glories are formed by light backward scattered and diffracted by small water droplets. Read quickly that is almost believable. The reality is more complicated. The classical ray path (below) through a water drop is impossible, the pieces do not join up. Surface waves are involved where the radiation travels across part of the sphere surface and a thin layer beneath.

The smaller the droplets, the larger is the glory. Experiment yourself with changing droplet size with the Lorenz-Mie scattering simulator IRIS.