The Halo Vault

Andreas Zeiske observed a pyramidal halo on 6 June 2011 in Frankfurt am Main. In the images, the 22° halo, 18° halo and the left 18° lateral...

The blog on atmospheric optics has moved to a new address ( 1 ), and has recently been updated with many interesting observations. As a tea...

The above image was photographed by Pitan Singhasaneh on 5 June in Bangkok, Thailand.

On 4 June 2011 Pietari Puranen observed these rainbows in Jyväskylä. When he turned around to see the sky around the sun, he observed an upp...

On May 1st 2011 cumulonimbus clouds precipitating hail were commmon. These clouds exhibited clear praecipitatio and later in the evening the...

The Finnish Astronomical Association URSA has just published a new book on halos by Marko Riikonen. This book combines the latest halo scien...

This Liljequist superparhelia was observed in the spotlight beam on 5 January 2011. The lamp is about a degree or two below the horizon, thu...