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.

Rare Halos in Japan

Hello from Japan.

In my web site, I have a log of halos and atmospheric optical phenomena observations.

Many (Japanese) people send me their observations, from ordinary ones like 22-degree halo to very rare ones.

Here I introduce two cases of odd radius halos in my site. I'm sorry that descriptions in the pages are written in Japanese, but you can see photos of halo displays anyway.

May 17, 2005, Odd Radius Halos in Yanai (top image of this article)

Wednesday, 15 February 2006

Diamond dust halos in Helsinki

Last weekend people in northern Helsinki were amazed to see "rainbows" and three suns in the sky. Here shown is one of the photos of the halo display by Timo Kuhmonen. See also the photo taken by Esko Lyytinen.

Tuesday, 14 February 2006

Great display in Switzerland

Here is a photograph of heavy class halo display seen in Davos on 20. December 2005. The photo is taken by Claudio Silberroth. More photos are at Bertram Radelow's site, which also displays some old drawings of halos.

Tuesday, 7 February 2006

Next 44° parhelia - in Stockholm

I found very nice photo of diamond dust display (on 3. January 2006) with 44° parhelion. Photo is used with permission of Yvonne Primé. All photos of the display are here. See also updated list of 44° parhelia occurrences. Two other reports from the same day are here and here.

Elliptical halo in Finland

This years first elliptical halo was seen on 4. February by Mika Aho in Muurame. The picture here shows fuzzy upper part of the ellipse on the edge of Altocumulus cloud.

Elliptical halos occur very close to the glare of sun and thus are not seen by accident – one has to look for them. They are often also short in duration. Appearances lasting less than a minute are not uncommon.

Because of closeness of the sun, dark glasses helps spotting elliptical halos. It also helps to know some clouds, since elliptical halos are usually formed in vicinity of Altocumulus. These clouds are made of supercooled water droplets at around -15° C but sometimes they precipitate ice crystals. It is in this icy virga that elliptical halos are observed (the white thin cloud in Aho photo). Mostly, though, Altoclumulus virga produces no elliptical halos. Certain level of dedicated sky watching helps to succeed in seeing them.

See more photos of the display and another ellipse last summer by Aho.

Friday, 3 February 2006

Diamond dust in Prague

Today (on 3. February 2006) Prague citizens had a nice morning surprise - diamond dust. HOP members (Tomas Trzicky and Katerina Juzova) and others observed bright sundogs, 22 deg halo, circumzenithal arc, faint parhelic circle and very nice 120 deg parhelia (see photo by Tomas Trzicky). Halos appeared even in an internet newspapers here and a guy called to the radio: "I see rainbows!". All photos and videos are here and here.

Thursday, 2 February 2006

Winter's best displays from Marko Mikkilä

Marko Mikkilä has opened a gallery for his halo photos. Shown are the best diamond dust displays from the nearby Louekallio ski resort snow machines. The gallery is still under construction, so keep checking.

The image here is from one of the Mikkilä's displays. It's caused by headlights of nearing car. This is actually stacked image from nine individual unsharp masked photos. The stacking program, Registax, was told to align the photos using the right parhelion. 

Above the car lights, there are two V-shaped arcs. The upper one is the common 22° upper tangent arc (perhaps with upper sunvex Parry arc), the lower one is Moilanen arc.

The Hastings display of Max Emerson

Max Emerson kindly informed that photos of the display he had seen in Swizerland are indeed available and that there is also short video.

Somewhat elusive in the video, the Hastings arc shows up better in this unsharp masked screenshot. Simulation (using HaloSim) by Patrik Trncak indicates many other rare halos as well. And of course, the display itself is outstanding in its brightness and clarity.