On 3 February, Milan Osecky observed a diamond dust display with sharp Moilanen arc by the village of Zaton. The halo was seen during sunrise, when the Sun was about 4° above the horizon. The phenomenon lasted approximately 8-10 minutes, starting at 8:05 and disappearing completely by 8:15. Also a diffuse sunvex Parry arc was observed, which was a bit difficult to distinguish from the upper tangent arc due to the fuzzy border between these two arcs.
Similarly, Tomas Trzicky in Jizerske hory observed well-defined pillars and upper tangent arcs in the light of street lamps ( 3 ).
Text: Martin Popek, Lukas Shrbeny