Finnish Halo Observers Network
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| 11 Jan 1999 South Pole, Antarctica |
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A great halo display at the South Pole in 11 Jan 1999 at 2.42 (NZST). |
| 21 April 1994 Siuntio, Finland |
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This great display was observed widely in southern and middle part of Finland. In these photos 9° and 24° column arcs were photographed. 24° column arcs were photographed for the first time (there is older photographs of them from the Neatherlands, but in that case they were not identified until lately. Also there is some photos of those arcs from Finland photographde in mid 1980's put that case was not known until late 1990's.) Those arcs are visible outside 22° halo at 24° distance in 11 and 1 o'clock directions intersecting 22° upper tangent arc. There was about 20 different halos on the sky at its best. There is only few displays outside Antarctica were as many halos has been observed at the same time. |
| 6 May 1993 Joensuu, Finland |
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A great odd radius display in Joensuu. Displays with rare concentric halos from pyradidal ice crystals can be seen only few times a year. In this display those usually faint and diffuse odd radius halos were bright and well developed. At the maximum of this display there were 7 concentric halos including 22° and 46° halos. With circular halos there is also odd radius plate arcs (or parhelia) as a brightenings or arcs. 9°, 18°, 23° and 24° plate arcs (or parhelia) can be seen in these photos. Plate arcs are formed when plate-like pyradidal ice crystal prefer an orientation instead of random orientation. |
| 8 April 1995 Helsinki, Finland |
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A display which was observed around southern Finland. In uniform high cloud layer shows a display were also rare 9° column arcs were observed. |
| 1 April 1994 Puolanka, Finland |
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In this display there was with ordinary halos a special kind of arc (it is probably too faint to see on screen). The arc is like a upper suncave Parry arc but its tips are bended downward and intersect 22° upper tangent arcs unlike normal Parry arc. These rare arcs follows Lowitz arc paths (in this case the upper (or Greenler's B component) Lowitz arc) and it should be think as one. |
