Wednesday, 27 August 2008
Report of the Czech 'Halo Observe Project' (HOP) about the past three months
Photographs above by Patrik Trncak and Martin Popek.
16th June 2008 - 120° parhelion
Tomas Trzicky observed a 120° parhelion during a flight over the Czech Republic. It was seen only briefly somewhere over the western part of the country while flying through cirrus clouds ( 1 ).
17th June 2008 - Elliptical halo in Holesov
Patrik Trncak, who observed the phenomenon in Holesov wrote: "It lasted a short time, a couple of seconds. The ellipse was complete, but the bottom quickly disappeared. It was observed on Ac virga, and irridescent clouds were seen, too." ( 2 )
20th June 2008 – Sunvex Parry arc in Prague
Monika Pacltova, who observed the phenomenon in the centre of Prague (Karlov) wrote: "Late afternoon I decided to make a time lapse video of the sunset with a 22° halo, bright parhelia and nice upper tangent arc. But... oh, damn! This simple and well-arranged display was all of a sudden 'badly spoilt' by a strange smudge above. Yeah, I saw the first Parry sunvex in my life". ( 3 - 4 - 5 )
24th June 2008 - Pyramidal halos in Prague
Stepanka Kosova observed in Prague-Uhrineves relatively strong 9° halo. Stacking a few pictures has shown other possible odd radius halos as well ( 6 - 7 - 8 ).
3rd August 2008 – Bottlinger's ring during a Prague-Moscow flight
Martin Popek wrote: "In the middle of the journey I observed a clear subsun. It was in a very low position almost beneath the plane. Nevertheless, I succesfully photographed a series of pictures which I stacked in Registax. Then the elliptical figure, similar to Bootlinger's ring was visible. By naked eye the phenomenon was seen as a veil around subsun. The phenomenon was observed on cloud type Ac translucidus perlucidus." ( 9 )
11th August 2008 – Suncave Parry arc and 120° parhelion in Morava
A number of observers saw a quite clear suncave Parry arc in the Czech Republic. This followed the previous observation of Parry arcs in Germany by the same cloud front. Martin Popek photographed 50 pictures, stacked in Registax ( 10 ). The suncave Parry arc was observed by Jan Kondziolka in Karvina as well ( 11 ). Martin Jankovic saw a nice 120° parhelion in Brno ( 12 ).
15-17th August 2008 – Halo meeting in Holesov
After two years, halo-phenomena observers in the Czech Republic held a meeting again. This time it was organised by Patrik Trncak in Holesov. Ten observers arrived during the weekend, and although the weather was not too favourable for halo observation, we spent the time successfully: we had lectures on rare halo phenomena and Registax, slide shows and consultations about photo-editing and the future of the Czech HOP project. Here are some photos at IAN.cz and the magazine Parhelium ( 13 - 14 ).
Text: Martin Popek, Monika Pacltova