Stills from a video by Olivier Vandeginste (optics site) travelling from Zurich to Brussels. Watch the video (YouTube) to see a fine impression of the changing size of the aircraft shadow as the cloud distance changes. While all that is happening the ringed glory - centered on where the shadow of Olivier's camera would be - stays almost constant. Glories, like rainbows and halos, do not occupy space, they are not real objects and unlike shadows they do not have linear dimension. A glory looks the same whether the droplets making it are at arms length or an infinite distance away. Droplet size is important though. Here tthe passing clouds must have had more or less of the same average droplet size. Images ©Olivier Vandeginste, shown with permission.
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