Odd radius display on sunset time, 2022-10-16 (Jouhe, France)

Often, when I see the clouds coming from west, I try to do a high cloud sunset to see if there is something to see (like sun pillar and sunvex halos).

this day, we had mosly contrails making here and there some ice halos from my position, but nothing unusual to catch the eye (furtive sundogs, 22° halos, upper tangent and maybe Lowitz buddies but too short in time to be exploitable) (Time-Lapse of part of the day in here, South-South-East Field of View). To find other halos at sunset, the exercice can be tricky, as the global backgroud turn progressivly to yellow then orange so the b-r rendering is more complicated, with adaptation to make in the last 30-45 mins before the end of sunset.
As I don't have automatized this, I find myself resigned to make one setting for the whole sequence to save time in my processings.
And sometimes, something catch my eye, as it did this last 16th of october, last year.
The three next images show 3 differents times of the event, with slightly different processings:

2022-10-16-[17h14à18h58]-NNW-bw-v1-[4-2]-UsM-(49)-5s5-histo-UsM-h20-h28?-h35

2022-10-16-[17h14à18h58]-NNW-bw-v2-[4-2]-UsM-(47)-7s7-UsM-histo

2022-10-16-[17h14à18h58]-NNW-bw-v2-[4-2]-UsM(56)-6s6-UsM-h28?-histo


If needed, I can provide the bw sequence, so you can see (as I do with VirtuaDub) the evolution of the display and distinguish the 28° halo with dynamic (back and forth) play on the sequence.

A sequence you will be able to see there (Version1 & Version2), but with the compression due to GoogleVideo. Again, all raw images are still in my possession, as I guess I might not be done with this display yet.

Display of 11th June 2017 in Pskov Oblast

Each frame of animation covers ten minutes

There were not rare halos during the display, exept for a weak upper 23° plate arc and a 9° halo. However, the display contained classic halo forms that were quite bright and long lived. I want to show you how these halos change their distance from the sun and curvature in nature. The thing that I remember most is the bright upper tangent arc, that was seen against a very thin ice cloud layer (1).

Display of 3rd August 2017 in Pskov oblast, Russia

Every frame of animation is stack which covers 2,5 min. Colored version is here

At the begining of the display, beautiful cirrus covered the sky, but I did not notice any halos at the time. When I came out a little later, I was surprised to see a bright parhelion and a middle Lowitz arc which crosses it! Cumulus limited the display, so I could observe halos only in gaps between these clouds. There was one short episode when I saw bright upper tangent and suncave Parry arcs. The following rare halos were found in the stacks:

 -well defined upper and middle Lowitz arcs (1) and possible lower Lowitz arc (2)
-part of helic arc (3)
-supralateral Tape arc (4)

Finnish Display 2nd September 2017

Kimmo Laitinen captured a nice display with Wegener arcs and a really strong lower tangent arc on the 2nd September 2017. I'll let Kimmo describe his observation in greater detail in his own words. 

He says, "we drove from Siilinjarvi to our summer house in Leppavirta via Kuopio. In Siilinjarvi the weather was sunny but before Kuopio a thin uniform layer of high clouds covered the sun and we spotted the first halos as we passed the city centre of Kuopio about 11.45.... At this point the 22 deg lower tangent arc was not so impressive and only a short section of the parhelic circle could be seen. Then we went on southward to the Puutossalmi cable ferry.... In Puutossalmi the 22 deg lower tangent arc was the most impressive and reflected nicely from the lake. After the ferry the 22 deg lower tangent arc disappeared but the parhelic circle became all the time longer and a very faint Wegener arc was seen by the naked eye. After driving a few km more southward the low clouds disappeared from the northern sky and the parhelic circle became complete about 12.30 in the village of Lansi-Saamainen in Leppävirta. The 120 deg parhelia were clearly visible and the intersection of the Wegener arcs with the parhelic circle was revealed from the images. After this the display got dimmer but still lasted for a few hours.

All images used by permission. © Kimmo Laitinen. 

Germania in Dove Bay

The etching shown above is based on the drawing of Austrian mountaineer, cartographer and landscape artist, Julius von Payer, and was published in the 30 December 1871 issue of Illustrirte Zeitung. The halo phenomenon was sketched in Dove Bay in the region previously known as King William’s Land, the northernmost area the Second German North Polar Expedition reached. 

In the mid-19^th century, German ambitions to explore to North Polar region resulted in two expeditions. The first, in 1868, got as far as latitude 81°5' near Spitsbergen, but could not reach its planned destination and yielded no significant scientific achievement. The second one was a more extensive journey and aimed at getting to know the central Arctic regions with a planned wintering in the hitherto unexplored northeastern Greenland. 

It was on 15 June 1869, when the two schooners, Germania and its supply vessel Hansa left Bremerhaven. The captain of Germania was Carl Koldewey, who had already gathered experience in polar journeys during the previous German expedition.  After about a month, the two ships met pack ice and got separated due to misreading the flag signs. Hansa was not fortunate: it was crushed by the ice and sank at latitude 70°32', a few kms from the Greenland coast. Its crew of 13 spent the winter in a coal dust briquette shelter and was finally saved. 

Germania, with its crew of 15 men, reached Sabine Island, where the wintering camp was established. In the autumn of 1869 and spring 1870, they made sledge explorations, reaching  the northernmost latitude of 76°30'N. The investigations were led by Payer and the most significant achievement was the discovery of Kaiser Franz Joseph Fjord, named after the Austro-Hungarian emperor, who had contributed to the expedition with significant donations. The return of Germania was adventurous. The engine broke, but finally she defeated pack ice, and managed to return to Bremerhaven on 11 September 1870, mostly by using sail.

The Illustrirte Zeitung article does not comment much on the peculiarities of the display witnessed by the explorers. It explains that parhelia are formed by the reflection of sunlight on ice crystals and then explains that sometimes a double ring and colourful arches may form, and even a horizontal line starting from the Sun (i.e.: the parhelic circle). The article then continues with praising the magnificent colours of the display. 

By Ágnes Kiricsi

Complex Halo January 21st 2017

On January 21st, after a long stretch of not getting any significant halos and not too long after observers in Hungary got a spectacular display, I observed a nice display here in the USA. The highlights of this one were the nice upper tangent arc and the 46 supralateral arc. I also got 120° parhelion too.

Lowitz - the new normal?

In 2017, halo activity in my part of the United Kingdom has so far been very quiet with not much to get excited about apart from the occasional odd radius lunar halo. However, on the 6th February things improved a little with a nice little display which included 22°, both parhelia (sporting parhelic tails), uta, possible Parry, cza, supralateral and all three Lowitz variants. The upper and lower Lowitz were vestigial, but the middle Lowitz illustrated here was quite clearly defined.

This burst of activity got me ruminating about the frequency of certain types of halos and the nature of “rarity”. Compared to many of you 'old hands', I am a comparative newcomer to halo observation. When I first started to observe, many halos were still considered to be extreme rarities or at least exceptionally infrequent. Others, such as the Kern, were so rare that they were considered to be the Holy Grail of halos, so few were their sightings. What I have noticed over the last few years is that many of these rarities are seemingly becoming far more frequent and in my own mind at least, I have downgraded them from ‘rare’ to ‘infrequent’.

Take the Lowitz arc for example. It is only a few short years ago that its very existence was being doubted, controversial to say the least. First, there were a few sightings, then a trickle of photographic images emerged which confirmed it as a reality. Over the past ten years, their frequency has seemingly increased to the point where I will see several per year and look out for them as a matter of course. Whilst not commonplace, they are certainly hovering somewhere in that vague, nebulous no-man’s land between infrequent and relatively frequent. Likewise, the Kern. At first a mythical creature, but now we are seeing the first drips which will eventually become a trickle….

So what has caused this apparent change in frequency, this downgrading of status? I would like to posit two possible causes: the ubiquity of digital imaging and advances in image processing. It is not that these halos are actually becoming more frequent in reality but that the effect of digital imaging and the development of image processing techniques are revealing them to be present in many more displays than were hitherto thought. In the past, one would take a roll of traditional film, but prior to image processing what did one do with them? Answer, nothing in most cases. You either saw the halo on a particular frame or you didn’t. This resulted in some of these rare halos only showing themselves under exceptional conditions. With the advent of inexpensive digital cameras and image processing software we saw far more phenomena being recorded. However, it is only with the introduction of the B-R processing technique pioneered by Nicolas Rossetto and perfected by Nicolas Lefaudeux and to a lesser extent image stacking, do we really notice an apparent increase in all types of rare halos. These techniques alone have been responsible for the massive increase of rare halo frequency and the identification of several new halo species. We have now reached a point where what was new and exciting yesterday, is passé today.

I think this trend is going to continue as more and more observers embrace these new methods of working. We have already seen it occur in the wider field of atmospheric optics where photographic identification of higher order rainbows, especially the third and fourth orders, are now becoming a reality. One might argue where is the hard evidence to prove this is anything but a theory or personal opinion? This evidence is indeed hard to come by, however projects such as Lefaudeux's 'HaloCam' has demonstrated without a shadow of a doubt that certain halos are far more frequent than previously thought. For example, he has very clearly demonstrated that the 46° halo is present almost as often as the 22°, whereas at one time it was considered to be a very infrequent visitor to the skies. So not only will this trend continue, I think it will also accelerate, especially in the field of spotlight displays where new halos are being discovered on a very regular basis. Even in daylight displays, new halos are still being captured from time to time using these techniques.

A few years ago, it seemed like everything that could be seen had been seen. We are now on the cusp of a new era of halo research. Today may indeed be considered passé by some, but tomorrow is definitely going to be tremendously exciting! I want to be a part of that new wave of discovery.

Alec Jones

Subparhelia and sub 120° parhelion on ice surface

average stack of 15 frames

In the morning after new year's night, I noticed through a window cirrus clouds, and I went to observe. While I was waiting for the appearance of halos, I noticed weak subparhelia on the ice surface. Out of curiosity, I decided to look for a place where they could be brighter, and I found it (1, 2). It was quite a small area near a coast, almost all sides limited. There I saw not only bright subparhelia, but also clearly visible sub 120° parhelion in pillar form.

maximum stack of 3 frames

It was perfectly visible even when I did not move. The temperature was negative only at night until this morning. In the previous day it was positive (around +4 degrees of Celsius), as during of the observation (0...+1). 

At that time, while I was shooting halos on the ice surface, in the sky appeared parhelion and 22 degree halo (3). Later the upper tangent arc was spotted in cirrus clouds (on the stack also well visible supralateral arc - 4). At the end of the day, I also noticed weak and wide circumzenithal arc (5) from low sun.

Date: 2017-01-01

The Salzburg halo

On the 19th October 2013 Zbyněk Černoch was in Salzburg keeping an eye for halo events, since high cirrostratus clouds were rolling in. As they drifted towards the Sun, he first noticed bright parhelia. A few moments later, rather bright and colourful upper tangent arc with Parry arc and upper Lowitz appeared.





What stunned him later was a vivid arc similar to a parhelion, but located in the 18° region.



The arc lasted only a few minutes as the clouds were drifting away quickly. He haven't seen anything like this before.

After a few discussions the observation fell into oblivion. Until few days later when we thought we would like to figure it out once and for all.

It would seem that the arc itself is a fragment of 22° halo, but the halo itself was quite sharp and narrow in this observation.

After Zbyněk put together 3 photos to show that the 22° halo lies between the mystery arc and 22° parhelion, I decided to run some simulations.

I used pyramidal crystals with std of 15° in the c-axis and joined the simulation picture with the collage from Zbyněk.



My theory is that the mystery arc is actually an 18° plate arc. But there are some inconsistencies in the theory.

1. The color vividness indicates that oriented crystals formed the arc. However 18° plate arc formed by oriented crystals has a typical convex shape which is absent here. 
2. By increasing the std in the c-axis, halos from poorly oriented crystals are becoming more apparent, which is not the case here. 
3. No other odd radius halos were observed. 

If it really is a case of an 18° plate arc, it is a really decent one.

High-Cloud Tricker from Hungary

January 16 brought a whole-day high-cloud display to the greatest part of Hungary. The morning started with a spectacular sunpillar with bright upper-tangent arc, and the phenomenon became more and more complex during the day. Perhaps the most interesting feature of the display was caught by Ernő Berkó. He saw a Tricker-arc in Ludányhalászi, Hungary.


As he explained, he started reading emails from other Hungarian observers about the beautiful sunpillar of the morning, but in his region, there was thick fog with a night temperature of -17 °C. At 12:10 UT the fog disappeared, and he discovered the upper-tangent arc and the then symmetrical (about 60 degree-long) supralateral arc above it. Both were slightly coloured. While he was making preparations to take photos, the clouds thickened and covered the view. Later the conditions turned better again, the right side of the upper tangent arc strengthened, and he could take photos from 13:15 for 25 more minutes with the supra reaching lower and lower. He could see that it got brighter at the place where the parhelic circle crossed the upper tangent arc. It was only later that he realised the infralateral arc was also a bit visible and this caused the brightening. Ernő Berkó was trying to discover other halo forms but until 13:20 there were no other arcs, not even a 22 degree halo. It was only after this that the 22° halo started brightening here and there; the clouds were not uniform at all. A few minutes later he caught sight of the halos at the anthelic point. What he saw was mostly of the time a white oval brightening only, but the Tricker-arc also appeared, and sometimes a faint X-shape was also visible, suggesting Greenler arcs. To the naked eyes. the parhelic circle was invisible at this region of the sky. Later on the phenomenon weakened as the clouds thickened again. Ernő said he felt lucky that some days earlier he had shovelled a path in the snow to the back of his garden (where otherwise his telescope is), as this was the place where he could take images without many disturbing objects in view…and he caught the Tricker here, too.



It was Csaba Kozsa, who managed to take a picture of the infralateral arc. He was also reading messages in the buzzing Hungarian forum of halo observers, so in the early afternoon he rushed to his favourite observation point: Visegrád’s hill, Kis-Villám. This is the closest elevation to his home with a good view to South-Southwest, and the 270m hill made it possible to take a photo of the infra. He says that up till this day he had had very little knowledge about complex halo phenomena, but thanks to the several observations on Monday and the explanations of more experienced observers, he now knows where to look and what to pay more attention to.

Halo Complex 15th October 2007

After over 90 days of above 90 degree temps and no halos this half-way decent display shows itsself in high clouds. Upon leaving work, I got quite a few photos. In all I got 22d halo, parhelia, upper tangent arc, bits of parhelic circle, infralateral arcs, 120d parhelia, and an upper suncave parry arc. While on the road I observed a rather bright 120d parhelion on the left side. As the patch of cloud shifted to the north the blue spot appeared and got several photos of it. When enhanced, the bluespot shows green, blue and purple and possible red but can't be sure. The one photo showing the Parry has ugly power lines but could not help that because I was shooting out the car window. If you wondering if I was driving at the time I wasn't because one should not drive and take photos at the same time. During those halo free days the temps were breaking records even in October and it was nice to see halos again.

 

by Michael Ellestad

 

Original post in Halo reports

Odd radius display

12th August 2007 - This day I can see interesting halo display. I thought that I could see upper tangent arc and inexpressive 22 degree halo. But the upper tangent arc was more and more brighter and lower tangent arc has not been seen. It crossed my mind that this phenomenon what i can see isn’t 22 degree tangent arc but 23 degree plate arc. I searched another pyramidal halos, but didn’t see it. Through that I took some photo. When I stacked and adjusted this photo was seen 9° halo, 18° halo, 23° upper plate arc and 22° or 23° halo. Lukas Kosarek

More photos: Martin Popek, Nydek (2.7.) , Stepanka Kosova, Prague (20.8.) and Jiri Los, Prague (20.8.)

By Patrik Trncak

The Beginning of Halo Season in Hungary

The halo-season in Hungary has began in a very promising way. There were two particularly noteworthy displays this week. 

The first one was observed by László Henez "Felhőcske" on 16th September near Eger, Hungary. As a born halo-observer, even though he was quite unaware of what he was seeing, he took a picture of not only the sunward halos, but the anthelic side, as well, where about a quarter of the bright white parhelic circle was visible together with a Wegener arc curving downwards towards the anthelic point. The 22° halo and the upper tangent arc were seen in the sky covered with uniform Ci for about half an hour after 8:25 UTC, while the anthelic arcs for only a few minutes. László did not see any 120° parhelia or anthelion. More of László’s photos can be seen here.

In the afternoon of 18th September, an odd radius display appeared with pyramidal 18° and 9° halos besides the 22° one. The photo was taken by "Controll" in Jobbágyi, northern Hungary, but the 18° halo was seen in Budapest by Alex Farkas, too. The display started with a 22° halo and lasted for roughly 40 minutes, until 14:15 UTC. "Controll" reported that she had seen a possible 46° halo as well, but it was at the edge of visiblity. It’s worth having a look at the faint pyramidal crystal parhelia in the picture provided. The full-size photo is also available, together with a panorama image of the display.

By Ágnes Kiricsi

Anthelic arcs in Finland

On August 28th anthelic arcs appeared in the northern part of Finland. My coffee break was suddenly halted as watching from the window I noticed several arcs. Once outside my eye was first caught by well developed parhelic circle. Then, looking up I noticed a colourful Wegener arc. Colours were red on the bottom and blue on the upper part. In the later stage of the display I noticed faint X at the anthelion indicative of the diffuse/Tricker arcs. I had no camera but my friend borrowed his camera equipped cellphone. Image quality is quite poor, but halos are still recognizable. Also Parry arc and 120 parhelia were present. Other halos were 22halo, parhelia, 22 upper tangent arc, parhelic circle, circumzenith arc, infralateral arc and supralateral arc. The display was noticed over large areas in Finland. More photos is here. Also see the photos by Arto Oksanen and Panu Lahtinen

By Marko Mikkila

Pyramidal halos 8-14-07

After weeks of seeing no nice halo displays I was at work today on breaktime and I saw 22 halo and upper 22 deg tangent arc. I put my sunglasses on and I soon realized I had an odd radius display at hand. In all there was 9 deg. halo 18 deg halo and the outer halo who knows it could be 22 or 23 or a combo of both. The upper arc is convincing it looks sharp and I think it might be 22deg upper column arc but not sure. One photo is an original and the other has USM applied to make the halos stand out better. This is a good odd radius display for me but I know there is a lot better.

Mid-elevation halo display with column crystals in control

Throughout my work day there were a number of halos that were coming and going. Around midday there was 22d halo, circumscribed halo, parhelic circle, and parhelia. Later on at break time I got 22 and circumscribed halos and there was a nice infralateral arc on the left and a possible lower suncave parry arc not sure on that need help to identify short piece of arc to the left of 22d halo. Before I left work I imaged an upper suncave parry arc. The final stage had nice upper tangent arc and a complete supralateral arc.

by Michael Ellestad

Diamond dust display in the Spanish Pyrenees

On January 26, 2007, Claudio Martinez watched and photographed a complex diamond dust halo display at the Baqueira Ski Station in the Spanish Pyrenees. Baqueira is situated at an altitude of 1850m. At about 5.30 pm CET the display showed the 22°-halo with sundogs, anextremely bright upper tangent arc, upper and lower sun pillar and the parhelic circle. Part of these was also visible in front of a mountain ridge. In the upper sun pillar there also appeared the Moilanen arc. Nearby floating ice crystals are also visible as bright sparks in the pictures.

There is also a video existing. You can see it here.

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.

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) .

Lunar Diamond Dust Display in Pälkäne, Finland

In the evening of 4 November this lunar display graced the sky soon after sunset. Among the halo forms observed are the rare heliac arc, Tape arcs and Moilanen arc. The Moon elevation is ca. 16°.

In the image the entire length of the heliac arc is visible as a beautiful loop encircling the zenith. The Moilanen arc is very intensive and appears to extend beyond the 22 degree halo. Tape arcs can be seen as diffuse brightenings on the supralateral arc.

In the beams of the passing cars a bright pillar, parhelia, upper tangent arc and Moilanen arc were clearly visible. These proved difficult to photograph though. At the local ski resort the snow guns were operating during the display and the crystal swarm was a by-product of this activity. The temperature was below -15 °C.

 

by Jari Luomanen

 

Originally in Halo reports