APOD: Sun Pillar with Upper Tangent Arc (2021 Feb 17)

[APOD Robot]

Sun Pillar with Upper Tangent Arc

Explanation: This was not a typical sun pillar. Just after sunrise two weeks ago in Providence, Rhode Island, USA, a photographer, looking out his window, was suddenly awestruck. The astonishment was caused by a sun pillar that fanned out at the top. Sun pillars, singular columns of light going up from the Sun, are themselves rare to see, and are known to be caused by sunlight reflecting from wobbling, hexagon-shaped ice-disks falling through Earth's atmosphere. Separately, upper tangent arcs are known to be caused by sunlight refracting through falling hexagon-shaped ice-tubes. Finding a sun pillar connected to an upper tangent arc is extraordinary, and, initially, took some analysis to figure out what was going on. A leading theory is that this sun pillar was also created, in a complex and unusual way, by falling ice tubes. Few might believe that such a rare phenomenon was seen again if it wasn't for the quick thinking of the photographer -- and the camera on his nearby smartphone.

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[JohnD]

Rare, no doubt, but one of the links takes you to a site with a photo of an identical phenomenon!
https://www.atoptics.co.uk/halo/colpill.htm includes an expanation of how the hexagonal crystals do it.

[orin stepanek]

Wow; a beauty for sure! I only remember seeing 1; It was from a setting sun behind the neighbors trees!

[smitty]

World's largest Golden Dream cocktail, perhaps? https://www.thespruceeats.com/golden-dr ... ipe-759302 .

[davidhumemoore]

Looks like a martini to me. Which Vonnegut said was the breakfast of champions.

[neufer]

<<Tangent arcs alter shape as the sun's altitude changes.

• (Mouse slowly over the slider to see them.)

Claudia and Wolfgang Hinz could observe the depicted halo phenomena, comprising not less than 22 types of halos, in the German Alps of Upper Bavaria

---

When the sun is on the horizon, both upper & lower tangent arcs are narrow 'Vs'. As the sun climbs the upper tangent arc opens and then droops like a gull's wings.

When the sun reaches 29º the upper arc links with the lower to become the "circumscribed halo".

The lower tangent arc narrows and then broadens again as the sun ascends. Of course, the lower arc is below the horizon when the sun is less than 22º high. Even so, it can still be seen from mountains or aircraft.>>

[JohnD]

Looks like a martini to me. Which Vonnegut said was the breakfast of champions.

Nah.
https://www.markarnall.com/breakfast-of-champions/

[johnnydeep]

<<Tangent arcs alter shape as the sun's altitude changes.

• (Mouse slowly over the slider to see them.)

Claudia and Wolfgang Hinz could observe the depicted halo phenomena, comprising not less than 22 types of halos, in the German Alps of Upper Bavaria

---

When the sun is on the horizon, both upper & lower tangent arcs are narrow 'Vs'. As the sun climbs the upper tangent arc opens and then droops like a gull's wings.

When the sun reaches 29º the upper arc links with the lower to become the "circumscribed halo".

The lower tangent arc narrows and then broadens again as the sun ascends. Of course, the lower arc is below the horizon when the sun is less than 22º high. Even so, it can still be seen from mountains or aircraft.>>

Very cool!

[pod_person]

What a lovely photo! My pictures aren't as pretty, but I've seen tangent arcs on sun pillars three times and managed to photograph them twice.

The first time was from Mauna Kea


The second and third times were both on ferry trips in British Columbia. I only had a camera with me on one trip and by the time I got it out, the tangent arc was barely visible.


I took more shots each time of course. All of them can be seen in this album, along with two photos of a tangent arc without a sun pillar taken from my home in Vancouver, and cell phone shots my wife took of a winter sun pillar in Saskatoon.

[BillBixby]

Two days later I feel my initial reaction ca be posted. The picture is wonderful but my mind is unsure if I am seeing cleavage or the back of a plumber bent over.