Clear air

Recently, there was a major front that passed over. Fronts are like air vacuums, cleaning the air. This happens because the dust in the air either forms cloud droplets or are absorbed by cloud droplets, the front then moves away with the dust or sends it back to the ground by rain. This is what happened, and the air is very clean. How can you tell? Usually there is an aureole around the sun by larger particles scattering light forward. It is typically a couple degrees wide, but if there is little or no aureole it means the air is really clean. In places in Antarctica or up above cirrus clouds, the effect is very striking.

Pileus, Shadows, and Colors 8/17 2010

My dad and I were by the river and were treated with a beautiful sky August 17 last year. There were large cumulus congestus clouds everywhere topped with pileus clouds. Pileus clouds tend to form all at once, meaning the droplets are of uniform size. That means good iridescence! And just that happened, I've not yet seen iridescence as good as this day. After that, long shadows were cast on the upper cloud layer.

Pileus clouds and planes

Beautifully iridescent cloud. This image has

not been enhanced in anyway.

Long cloud shadows

Another dewbow!

I saw another dewbow this morning, it was much better than my previous observation. It was much brighter than in the picture, and showed very well as you moved, very obvious.

See the faint arc?

Tiny Dew Bow

I observed a small dew bow in a spider web connecting a few blades of grass. Standing up, it showed bits of color as you moved your head.

Unfocused image, if the image is focused it

is practically invisible.

Heavily unfocused, see the colors?



Rare halo display in Fall

I observed a spectacular halo display the 12th of November. You can see this display on OpticsPOD, this post just has more pictures of the halos.

The halos observed were:

• 22 degree halo
• Sundog
• Circumzenith arc
• Upper tangent arc/circumscribed halo
• Parry arc
• Parhelic circle
• 120 degree parhelion
• Supralateral arc
• Infralateral arc
• 46 degree halo
• Lowitz arc
• Wegener arc

Displays like this will happen, as long as you keep looking for them!

Parhelic circle

Infralateral arc (look carefully!)

Upper tangent, Parry, and Lowitz arcs. This halo

was much brighter than appears in the image.

Wegener arc, the image has been unsharp masked

so the rare halo shows up more clearly.

Later in the day, a CZA and supralateral

arc appeared in the sky.