Halos, Architecture, Geometry, Time ~ Prague, Czech Republic imaged all on the same afternoon by Mario Freitas (site) of Universidade Tecnológica Federal do Paraná, Brazil. ©Mario Freitas, shown with permission.
Atmospheric
Optics

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Geometry and time are the essence of ice halos and their product is beauty in the skies.

The best of architecture is similarly underpinned. That of Prague spans at least seven centuries.

At top, twin sundogs and a parhelic circle. The sun is shielded by the Gothic Old Town Hall Tower with parts dating from 1338. Prague’s famous astronomical clock stands near its base and has run continuously since 1490. It is the page’s backdrop.

At left the parhelic circle above the Old Town Square. A mimicking cloud streak illustrates how this colourless halo is often difficult to distinguish in cloud wisped skies. The right hand building is the Goltz-Kinsky Palace in Late Baroque Rococo style built 1755-65. Franz Kafka studied at the grammar school housed in the palace.

Lower left jumps to the 20th Century with an Art Nouveau façade in the Old Jewish Quarter. Horizontal plate crystals make their presence known via a circumzenithal arc.

Lower image: Iridescent clouds where diffraction signals a departure from the order and dictates of geometrical optics. The 20th Century sculpture marks the 500th anniversary of the church reformer Jan Hus’s burning to death for heresy 6th July 1415.