Showing posts with label 22° lunar halo. Show all posts
Showing posts with label 22° lunar halo. Show all posts

Tuesday, 7 March 2017

Snow gun generated column display



On the night of 15th November 2016 (the night of the "supermoon") I was out of the city photographing the full Moon. The humidity was extremely high, which was evident by a huge aureola that was surrouding the Moon.


I was keeping an eye on webcams located at nearby ski centres, because the temperature was dropping below zero and snow coverage was scarce, therefore I was hoping for some snow gun action.

Few centres were operating the snow guns, but no diamond dust formation could be seen, so after a while I decided to return back to the city, but still keep an eye in case the conditions change. According to my previous post, Bílá ski centre is supposed to be the holy grail of diamond dust halos around here. But that is not true, there is another ski centre which generates diamond dust very frequently. I stayed up the whole night because I knew something would happen, and I was right, the ski centre I was talking about started generating halos, so I packed up my things and went again.
It is slightly further away than Bílá, so the trip took a while, but it was totally worth it:


This display, to my astonishment, was generated by a single snow gun (in the picture above it is located just behind the trees). No low hanging stratus, just high humidity and one snow gun. And it wasn't even on my previously planned location, it was actually a few kilometers ahead of it.
There are some indications of Parry oriented crystals, uppercave Parry is present and lowercave maybe too. indicated by a brightening on the circumscribed halo. Lowervex Parry was not seen. Wegener was maybe there, but the display itself was changing quite rapidly and I don't think my photos captured it.

Eventually I have decided to finish driving to my location. No halos there, and as I was returning, only faint and diffuse 22° halo was the only one left in the sky.

The crystal swarm was fairly thick, which can be seen in the main photo - the infralateral arcs were hanging in front of the forest. An amazing sight.


Fun addition: I had actually forgotten my gear at the location, and only realized it at home, so I had to return. It was still there!

Saturday, 6 January 2007

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) .

Monday, 13 November 2006

Lunar display in Switzerland


On Nov/11/2006 I observed a nice high moon halo display in Switzerland. Visible was a bright circumscribed halo and a infralateral or circumhorizon arc.
 
by Mark Vornhusen
 

Wednesday, 8 November 2006

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
 

Friday, 17 March 2006

Thursday, 16 March 2006

Latest halo displays from Finland




















During the last days series of reasonable displays developed over Southern Finland. Three of them were in moonlight and one in sunlight. Elliptical halo, 9° and 18° halos and Parry arc were observed. See photos and drawings here.

The picture on the left shows the halo development in Tampere on the night of 14/15 March. Among common halos, faint 9° halo and Parry arc are also present.

By Marko Riikonen

Saturday, 18 February 2006

Tranquility of simple winter Moon halo


With all the bright complex displays and rare halos presented here, it's possible to forget that even a simple display can be a beautiful sight. Marko Mikkilä photographed this 22° halo from his backyard a couple of days before last full moon.




In moon halo photos sky tend become smooth as clouds move during exposure. Here smoothness is further enhanced by stacking seven individual shots.