Sunday, 21 October 2007

Elliptical Halo in Vecsés, Hungary


Today on 21st October at 11:27 local time I saw this elliptical halo above Vecsés, Hungary. I was photographing Ac len and iridescent Ac clouds, when I caught sight of the display. The elliptical halo formed on the ice crystal precipitation of one of the Ac. The display lasted less than two minutes, so I really had to hurry to find a good object to shield the Sun with, and not to miss the sight meanwhile. In the first photo - I was still using the neighbouring house's wall, - even the reddish inner side of the halo can be seen. More photos.

Elliptical Halo in Vecsés, Hungary


Today on 21st October at 11:27 local time I saw this elliptical halo above Vecsés, Hungary. I was photographing Ac len and iridescent Ac clouds, when I caught sight of the display. The elliptical halo formed on the ice crystal precipitation of one of the Ac. The display lasted less than two minutes, so I really had to hurry to find a good object to shield the Sun with, and not to miss the sight meanwhile. In the first photo - I was still using the neighbouring house's wall, - even the reddish inner side of the halo can be seen. More photos.

Elliptical halo in Vecsés, Hungary


Today on 21st October at 11:27 local time I saw this elliptical halo above Vecsés, Hungary. I was photographing Ac len and iridescent Ac clouds, when I caught sight of the display. The elliptical halo formed on the ice crystal precipitation of one of the Ac. The display lasted less than two minutes, so I really had to hurry to find a good object to shield the Sun with, and not to miss the sight meanwhile. In the first photo - I was still using the neighbouring house's wall, - even the reddish inner side of the halo can be seen. More photos are also available ( 1 )

Austrian halo display with Parry arc


On October 9, 2007, my husband and I made a trip to Austria to visit the highest mountain of that country, Mt. Großglockner, 3798m ( 1 ). The main ridge of the alps gave a warm welcome to us with a bright and diffuse fragment of the infralateral arc ( 2 ). Just a little later, at a sun elevation of 33.4°, a sharply defined Parry arc ( 3 ) formed directly above the upper tangent arc. There were only few occasions that we saw it in such a brightness before. The beautiful halo display was completed by sundogs ( 4 ) and an almost complete parhelic circle ( 5 - 6 ). Even the heliac arc seemed to be present, as we both recognized it. The cirrus clouds, however, showed a very striated structure, so it cannot clearly be identified in our photographs.

In the afternoon, at a sun elevation of 30.9°, a fragment of the parhelic circle appeared in a narrow cirrus fiber together with a bright 120°-sundog. This sundog not only had a greenish and reddish rim ( 7 ), but also showed a striking vertical extension from time to time. Below it there seemed to be kind of cross-formed arcs ( 8 ) like those which normally appear around the anthelion only.

Text: Claudia Hinz

Austrian Halo Display with Parry arc

On October 9, 2007, my husband and I made a trip to Austria to visit the highest mountain of that country, Mt. Großglockner (3798m). The main ridge of the alps gave a warm welcome to us with a bright and diffuse fragment of the infralateral arc. Just a little later, at a sun elevation of 33.4°, a sharply defined Parry arc formed directly above the upper tangent arc. There were only few occasions that we saw it in such a brightness before. The beautiful halo display was completed by sundogs and an almost complete parhelic circle (with unsharp mask). Even the heliac arc seemed to be present, as we both recognized it. The cirrus clouds, however, showed a very striated structure, so it cannot clearly be identified in our photographs.


In the afternoon, at a sun elevation of 30.9°, a fragment of the parhelic circle appeared in a narrow cirrus fiber together with a bright 120°-sundog. This sundog not only had a greenish and reddish rim, but also showed a striking vertical extension from time to time. Below it there seemed to be kind of cross-formed arcs like those which normally appear around the anthelion only.

Austrian Halo Display with Parry arc

On October 9, 2007, my husband and I made a trip to Austria to visit the highest mountain of that country, Mt. Großglockner (3798m). The main ridge of the alps gave a warm welcome to us with a bright and diffuse fragment of the infralateral arc. Just a little later, at a sun elevation of 33.4°, a sharply defined Parry arc formed directly above the upper tangent arc. There were only few occasions that we saw it in such a brightness before. The beautiful halo display was completed by sundogs and an almost complete parhelic circle (with unsharp mask). Even the heliac arc seemed to be present, as we both recognized it. The cirrus clouds, however, showed a very striated structure, so it cannot clearly be identified in our photographs.


In the afternoon, at a sun elevation of 30.9°, a fragment of the parhelic circle appeared in a narrow cirrus fiber together with a bright 120°-sundog. This sundog not only had a greenish and reddish rim, but also showed a striking vertical extension from time to time. Below it there seemed to be kind of cross-formed arcs like those which normally appear around the anthelion only.

Wednesday, 17 October 2007

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.












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.












Wednesday, 10 October 2007

Complex Halo Display with Wegener´s anthelic arcs in Germany

In the early afternoon of July 8, 2007, Reinhard Nitze could observe the most extensive halo display with 8 different halo types he had ever witnessed.

The most interesting feature of the display was probably the appearing of the anthelion with Wegener´s anthelic arcs attached to it. The left part of Wegener´s anthelic arc was clearly visible to the naked eye, but in the photographs also the right part seems to be faintly visible. One picture, processed by an unsharp mask, even gives the impression of a faint “halo-X” on the parhelic circle. The 120°-sundogs, were clearly visible too.

Also the other side of the sky around the sun looked interesting. The sun was surrounded by a faint 22°-degree halo, and on top of it there was a bright and colourful upper tangent arc respectively circumscribed halo with a Parry arc attached to its upper side. As the circumscribed halo crossed the sundogs exactly, I first thought of the Lowitz Arc (erroneously). Both sundogs were visible, the left one for a short time very bright and colourful. The parhelic circle was faintly visible even inside the 22°-halo on the left side. But this part of it it was not very bright. At its largest extension, two thirds of the parhelic circle were visible. Unfortunately, low clouds often disturbed the observation.

Complex Halo Display with Wegener´s anthelic arcs in Germany

In the early afternoon of July 8, 2007, Reinhard Nitze could observe the most extensive halo display with 8 different halo types he had ever witnessed.

The most interesting feature of the display was probably the appearing of the anthelion with Wegener´s anthelic arcs attached to it. The left part of Wegener´s anthelic arc was clearly visible to the naked eye, but in the photographs also the right part seems to be faintly visible. One picture, processed by an unsharp mask, even gives the impression of a faint “halo-X” on the parhelic circle. The 120°-sundogs, were clearly visible too.

Also the other side of the sky around the sun looked interesting. The sun was surrounded by a faint 22°-degree halo, and on top of it there was a bright and colourful upper tangent arc respectively circumscribed halo with a Parry arc attached to its upper side. As the circumscribed halo crossed the sundogs exactly, I first thought of the Lowitz Arc (erroneously). Both sundogs were visible, the left one for a short time very bright and colourful. The parhelic circle was faintly visible even inside the 22°-halo on the left side. But this part of it it was not very bright. At its largest extension, two thirds of the parhelic circle were visible. Unfortunately, low clouds often disturbed the observation.

Sunday, 7 October 2007

Concave & convex Parry arcs photographed in Georgia

A visitor of my homepage emiled me this photo of a complex display that took place in Rome, Georgia and the year I can't remember but it was in the early 90's and of all the halos the bright upper concave and convex parry arcs are the most interesting. This is probably the best I have seen where both upper parry arcs are visible . Other images show a bright supralateral arc as well. The person who sent the photo is Loren Hall and his email is: bctimebandit@earthlink.com

Concave & convex Parry arcs photographed in Georgia

A visitor of my homepage emiled me this photo of a complex display that took place in Rome, Georgia and the year I can't remember but it was in the early 90's and of all the halos the bright upper concave and convex parry arcs are the most interesting. This is probably the best I have seen where both upper parry arcs are visible . Other images show a bright supralateral arc as well. The person who sent the photo is Loren Hall and his email is: bctimebandit@earthlink.com

Blue spot gets more colours


Blue spot is the colour feature of the parhelic circle occurring at the anthelic region of the sky. In addition to the blue, the theory predicts also green, but no red. Yet in several observations also red colour has been reported. However, because the red has never reproduced in photos, the observations have been doubted.

The image here shows two versions of a simulation of plate crystal parhelic circle in the anthelic region of the sky. The upper one has not been processed, the lower one has an overall levels adjustment to enhance colours. It looks like there is red present in addition to blue and green.

So it may be that observations of red may have not been wrong after all and that the theory (and naming) of the blue spot needs to be reconsidered. Lacking of the red in photos may be explained by film and sensor sensitivity issues. Even though the colors are seen with naked eye, they are still weak and some wavelenghts may be more prone than others to be not captured by the photographing equipment.

The simulation was made with a software developed by Jukka Ruoskanen. Sun elevation for the simulation is 25°, the plates have aspect ratio of 0.9 and tilt 3°.

Blue spot gets more colours


Blue spot is the colour feature of the parhelic circle occurring at the anthelic region of the sky. In addition to the blue, the theory predicts also green, but no red. Yet in several observations also red colour has been reported. However, because the red has never reproduced in photos, the observations have been doubted.

The image here shows two versions of a simulation of plate crystal parhelic circle in the anthelic region of the sky. The upper one has not been processed, the lower one has an overall levels adjustment to enhance colours. It looks like there is red present in addition to blue and green.

So it may be that observations of red may have not been wrong after all and that the theory (and naming) of the blue spot needs to be reconsidered. Lacking of the red in photos may be explained by film and sensor sensitivity issues. Even though the colors are seen with naked eye, they are still weak and some wavelenghts may be more prone than others to be not captured by the photographing equipment.

The simulation was made with a software developed by Jukka Ruoskanen. Sun elevation for the simulation is 25°, the plates have aspect ratio of 0.9 and tilt 3°.

Saturday, 6 October 2007

Lowitz Arc in Bochum, Germany

On September 6, 2007, Peter Krämer observed a relatively bright left Lowitz arc in the skies over Bochum in the German Ruhr area. The arc (picture with unsharp mask) stayed visible for about 20 minutes, stretching away upwards and downwards from the left sundog.
Apart from the sundogs and Lowitz arc, there was also a faint 22°-halo visible, together with the upper tangent arc and circumzenital arc.
One hour later, after Lowitz arc and CZA had already faded away, the upper tangent arc became rather bright, and also parts of the supralateral arc showed up.

Lowitz Arc in Bochum, Germany

On September 6, 2007, Peter Krämer observed a relatively bright left Lowitz arc in the skies over Bochum in the German Ruhr area. The arc (picture with unsharp mask) stayed visible for about 20 minutes, stretching away upwards and downwards from the left sundog.
Apart from the sundogs and Lowitz arc, there was also a faint 22°-halo visible, together with the upper tangent arc and circumzenital arc.
One hour later, after Lowitz arc and CZA had already faded away, the upper tangent arc became rather bright, and also parts of the supralateral arc showed up.

Wednesday, 3 October 2007

46° contact arcs


About a year ago in Muonio, Finland, a diamond dust display produced a new halo, the 46° contact arcs. The display was shortly reported in the blog, but no simulation was shown. So here is a simulation, together with a composite of the photos that were taken by Päivi Linnansaari. The 46° contact arcs, which arise from Lowitz-oriented crystals, appear as three arcs below the circumzenith arc.

The Lowitz crystals used in the simulation are regular plate-like hexagons, with aspect ratio of 0.4, tilt about the Lowitz axis 28° and Lowitz axis rotation 1°. Sun elevation is 9°. The Lowitz arcs themselves are faintly visible at 10 and 2 o'clock positions, separating from the 22° halo and reaching towards the upper sunvex Parry arc. This is the circular component of the Lowitz arcs, also known as the c-component (after Greenler).


Occasionally, in high cloud displays there is seen a short patch of 46° halo under the circumzenith arc, as shown here in the photo by Stepanka Kosova, taken on 20 August in Prague. It has been sometimes suspected that these might be indications of 46° contact arcs. Whether that's the case, it may be confirmed if a series of photos are taken for stacking.

The simulation is made with HaloSim by Les Cowley and Michael Schroeder.

46° contact arcs


About a year ago in Muonio, Finland, a diamond dust display produced a new halo, the 46° contact arcs. The display was shortly reported in the blog, but no simulation was shown. So here is a simulation, together with a composite of the photos that were taken by Päivi Linnansaari. The 46° contact arcs, which arise from Lowitz-oriented crystals, appear as three arcs below the circumzenith arc.

The Lowitz crystals used in the simulation are regular plate-like hexagons, with aspect ratio of 0.4, tilt about the Lowitz axis 28° and Lowitz axis rotation 1°. Sun elevation is 9°. The Lowitz arcs themselves are faintly visible at 10 and 2 o'clock positions, separating from the 22° halo and reaching towards the upper sunvex Parry arc. This is the circular component of the Lowitz arcs, also known as the c-component (after Greenler).


Occasionally, in high cloud displays there is seen a short patch of 46° halo under the circumzenith arc, as shown here in the photo by Stepanka Kosova, taken on 20 August in Prague. It has been sometimes suspected that these might be indications of 46° contact arcs. Whether that's the case, it may be confirmed if a series of photos are taken for stacking.

The simulation is made with HaloSim by Les Cowley and Michael Schroeder.