Complex displays in Eastern Europe

A series of complex halo displays occured in Eastern Europe between 27 March and 6 April. The first display in this series was seen in Vecsés, Hungary (observer: Ágnes Kiricsi). On 27 March at 13:30, after the appearance of the shining 22° and circumscribed halos, the parhelia started getting brighter and brighter, and together with them, a growing stretch of the parhelic circle came to sight ( 1 ). In about a quarter of an hour, as the clouds were passing towards the east, the 120° parhelion showed up on the left ( 2 ). The phenomena lasted until 14:10 with the complete parhelic circle visible for about 5 minutes.

The display continued until sunset with a 22° halo, parhelia, upper tangent arc, circumzenith arc and supralateral arc. In Vecsés, the clouds started thickening, but in Budapest the conditions got better at this time of the day. In a rather narrow stretch over the capital, a Tape arc was observed between 16:40-16:56. Images were taken by Alexandra Farkas and Tibor Hollósy ( 3 and enhanced 4 ). They did not see other halos formed by Parry oriented crystals, but 7 km to the north and only 3 minutes earlier, Márk Laczkó had photographed an upper suncave Parry arc ( 5 - 6 ).

In Hungary, there were two other observations of complex displays with complete or almost complete parhelic circles. One on 1 April (Ágnes Kiricsi in Vecsés), the other one on 5 April (Alexandra Farkas, Tibor Hollósy in "Remete" Gorge).

On 2 April, after a long time period, Marko Krusel also had an opportunity to observe a complex halo display in Estonia, nearby Keila. The peak time was 14:30, when the sun was 30.9 degree above the horizon and the sky was covered by cirrostratus haze. Besides all the common halos like 22° halo, upper and lower tangent arcs, parhelia, supralateral arc and CZA, he also got a bright upper suncave Parry arc, a nice full parhelic circle and 120 degree parhelia. A fragment of the infralateral arc was also seen on left. The show ended at 16:00.
Suprisingly the right side parhelic circle and 120 degree parhelion were the latest leavers ( 7 ).

6 April was a favourable day for the Czech Republic and Poland. The Czech Matej Grek (Ostrava-Dubina) and Martin Popek (Nydek) both photographed complex displays with parhelic circles and bright circumscribed halos. A 46° halo was also visible ( 8 - 9). On the same day, Jakub Marchewka also observed rare halos in Chrzanów in the south of Poland. He saw well-defined 22° halo with parhelia, circumscribed halo and full parhelic circle on cirrostratus ( 10 - 11 ). When he looked through the photos he had taken, he noticed a faint Wegener arc ( 12 and enhanced 13 ) and 46° halo ( 14 and enhanced 15 ). It was a first observation of Wegener in Poland and one of the first of 46° halos. On 20th February 1661 Johannes Hevelius observed the Gdańsk halo display and he described a 46° halo. If he was right and did not mistake it for supralateral arc and infralateral arc, Jakub Marchewka's observation is the second in Poland.

Text: Marko Krusel, Jakub Marchewka and Agnes Kiricsi

Sky halos in southern Germany

Although this year only few haloes appeared over Germany, I could observe the second complex halo display on Mt. Wendelstein ( 1 ). In the morning I saw my first subsun ( 2 ) in this year, which appeared in freezing fog. Later a veil of cirrostratus from a low pressure area over the Mediterranean Sea crossed the Alps from the south. Under those weather conditions, large halo displays can be seen very often. In my own statistics, 80% of all larger halo displays appeared when there was a southerly stream of air over the Alps, or under foehn conditions. And also this time there was a large choice of haloes ( 3 ) in the southern part of the sky, which lasted for about two hours and a half. Between 10.10 and 12.45 CET the 22°-halo, a bright upper tangent arc and a faint Parry arc, both sundogs with Lowitz arcs, the parhelic circle, an almost complete supralateral arc, a faint infralateral arc on the right side, and a complete sun pillar were visible. Unfortunately, the haloes appeared only over a small area on the northern rim of the Alps. So except of me, only my husband who was down in the valley at that time, could enjoy similar halos ( 4 ).

Text: Claudia Hinz

Giving better looks for the stacked images

There is no denying it - stacked and unsharp masked halo image can be rather ugly. Ground objects are blurred and horizon is coated with blue glow.

But the looks can be improved by taking the ground from single untreated frame. That's what is done in the upper right image. It is the same image as the upper left except for the ground.

Near the horizon the clouds from the single frame dominate the sky, but in this case it has no significance as the halos are anyway blurred at the horizon. This technique works best with high sun displays where halos are far from ground objects.

The display was seen in Lahti on June 9. The upper image pair is stacked (using Registax) from 72 frames taken during 15 minutes. The lower is 60 frames /12 minutes stack. It shows lower 24 plate arc on the right and perhaps some 24 halo on the left. Jukka Ruoskanen also photographed the display some 40 kilometres from Lahti. Another example of the ground adding is here.

Odd radius halo 6-19-07

While at work on break time I noticed there were cirrus clouds in the sky and I decided to check for halos and I got three odd radius halos which were 9, 18 and 22 or 23? degree rings. I took a few photos. I unsharp masked one of them the show the halos more clearly. This was probably the only halo highlight of June but nothing super special but it beats nothing.

Moon pyramidal halo complex in Czech Republic

In June when conditions for observing halos aren’t fine because of low full moon elevation, I have had my best observation ever. On cirrostratus veil divided from cumulonimbus cloud firstly appeared 9° halo and later thick halo at 22-24 area. After stacking 20 pictures, it turned out to be 23° and 24° halo. Fragments of 20° halo were not recognizable until stacking photos. Halos were seen at the highest intensity for about half an hour.

Martin Popek

Odd radius halos at Crete

These odd radii were a little bit surprising, I didn’t expect something like this at Asimenia beach in Kavroz. I had been waiting for any halos for five days and the first display was directly pyramidal 18°, 20° and 23° halos. Fortunately I had a piece of welding glass because photos I took without this protective glass was totally unusable because of reflections. The display originated at very thin cirrus clouds.

Martin Popek

Subparhelia with reflected Lowitz arcs

Bill Burton, USGS, observed nice halo display with very rare reflected Lowitz arcs. Bill: "This photo showing an impressively bright sub-Sun and sub-parhelion was taken from the window of a commercial airliner on a flight from Anchorage to Minneapolis. I was looking down at a thin, cirrus cloud layer over the snow covered farmland of southern Canada when these wonderful halos and arcs appeared. The Sun is above the image, producing this sub-Sun and upward-facing portion of a 22-degree halo. This sub-Sun was brilliant enough to create its own sub-parhelion and 22-degree arc - on the right side of the image. Photo taken on January 11, 2007"

Text was assumed from EPOD