2007. január 15., hétfő

Moilanen arc display with cell phone camera

Jaakko Tähti photographed this moderate display with Moilanen arc on 12. January 2007 in Viitasaari. "The halo display lasted for about four hours and changed constantly. It was a pity I was working inside. At times however I went to take some pics", says Tähti who used his cell phone camera for photographing. The vague double structure in the upper tangent arc seems to indicate that the display contains also an upper sunvex Parry arc.

The following night diamond dust was drifting also in Tampere and Hyvinkää. See the divergent light halos by Jari Luomanen and Jukka Ruoskanen.

2007. január 6., szombat

Moon halo over Southern Finland - oriented columns in command

Little after midnight on the night of 5-6th January a fairly bright 22 halo and upper tangent arc appeared in high clouds. At this stage nothing implied that anything better would be on the way. However, at around 1.30 a.m. the halos arising from oriented columns had got much better and upper and lower tangent arcs stretched out to form a circumscribed halo. Infralateral arcs and a 9 halo appeared as well. Judging from the quality of circumscribed halo and infralateral arcs at the maximum phase one might suspect that rays scattered by oriented columns may have partially contributed to the intensity of the 9 halo.

The display ended at around 4 a.m. when low level clouds rolled in. Shortly before that 46 halo and parhelic circle were well formed (although faint). According to the reports so far the display was best seen in Tampere (photos by Jari Luomanen) and in Riihimaki (photos by Jukka Ruoskanen) .