Very large coronae were observed in Southern Finland at the beginning of May 2006. Their radius was about 45° and they had a bluish disk and a brown ring. The sky was very clear and quite dark outside the corona. Also, very beautiful red sunsets were seen on those days.
The phenomena were visible on many days between May 2-11 and were possibly produced by smoke carried from Eastern Europe.
In the above corona image taken on 11th May a small segment of another photo has been added to show the size of 22° halo for comparison.
The sunset was photographed on 4th May.
Large coronae can be seen during very warm weather periods when the sky is usually hazy. This was the first large corona seen in Finland since the Bishop’s rings of 1991-1992. Smaller coronae (radius of about 5°) with a blue disk and brown ring have sometimes been observed.
[Text & Report: Jari Piikki, Juva Finland]