Moscow Spiral Contrail / Helix Cloud - Theories

[Mick West]

From this site (but likely not to stay on this page)
http://netall.ru/gnn/photo_day/

The original text is:

1- Небесная спираль. Утро 24 декабря 2012 года, Крюковская эстакада. Фото прислал donskoi92

2 - Небесная спираль. Утро 24 декабря 2012 года, Солнечная аллея. Фото прислал donskoi92

3 - Небесная спираль. Утро 24 декабря 2012 года, 20-й микрорайон. Фото прислала Наталья

4 Небесная спираль. 24 декабря 2012 года, Савелкинский проезд. Фото прислал MUTANT

Translation

1 - Celestial spiral. Morning of December 24, 2012, Kryukovskaya Pier. Photos sent donskoi92

2 - Celestial spiral. Morning of December 24, 2012, Solar alley. Photos sent donskoi92


3 - Celestial spiral. Morning of December 24, 2012, the 20th district. Photos sent Natalia


4 Celestial spiral. December 24, 2012, Savelkinsky fare. Photos sent MUTANT

Here's my initial take on it, as posted on ATS:

That's a very interesting contrail.

One of the common mistakes people make when looking at contrails is to assume that the way it ends up is the way that it started. Contrails do NOT mark the track of a plane, unless the air is perfectly still and calm, which it never is. Contrails are blown sideways by the wind so they are at an angle to the actual track of the plane. They also sink so they are below the track of the plane. They spread out to cover an area much wider than the track or the plane.

And sometimes they rotate. They rotate, not because the plane is rotating, or flying in a spiral path, but because the AIR is rotating. Air is a fluid, an it acts like a giant ocean. Sometimes you get waves in this ocean, which contain huge rotating regions.

If a plane flies through such a region of rotation, then the contrail, which starts out straight, will end up twisted, if it stays in it long enough, then it might twist more that once. Normally these twists are fairly long.

I don't know if such a rotating region of air formed the Moscow twist. It does look like there are two contrails. However it could just be that the bottom edge of a sinking contrail was thick enough to look like a separate contrail. It could be that two jets were flying together (not in a spiral), and then the rotating air wrapped their contrails together.

Have a look at these clouds. You can see the huge rotating regions of air because they are above a fog layer, and the fog layer gets sucked up into these wave shapes:

But then imagine this scene is much higher up, and there are no clouds there. But the "waves" are still there, the air is still rotating, you just can't see it. Then a plane (or maybe two) flies right through the middle of one of those regions, hits a spot of higher humidity, and leaves a short contrail, which gets twisted, maybe ending up like the Moscow twist.

I'm not sure what this is. Any more suggestions?

[UPDATE] It seems almost certain that this is a very long twisted contrail viewed end on, see below.

 

[Mick West]

In photos 1 and 2, taken by the same person, the same building appears:

Looking at the light here I'd say it looks like a high cloud, contrail altitude. It's lit bright white, whereas the clouds lower in the frame are orange with the rising sun. There's also a linear contrail in #2 that is the same pure white.

Comparing #1 and #2, #2 is bigger, there's also a tilt. but that might just be the camera position.

It's possible that #2 is bigger than #1 because the camera is closer. However it could also be because the cloud has spread a bit more. It does not seem to have changed shape, in terms of more twist.

 

[JFDee]

It's probably worth to note that Moscow has remarkably cold weather at the moment.

 

[Mick West]

Some more examples from"QuickBlackFox",

http://www.abovetopsecret.com/forum/thread912032/pg3#pid15623577

First of all, my own pictures, this is from a few years back (Kyiv, Ukraine):

Each of these was left by a different plane. I've got pictures of a few more - the entire sky was full of these spirals, we have a major navigation point nearby.

These were absolutely normal jet planes flying up high. I've got a close look at half of jets leaving those trails. You can see that on last picture, the spiral is quite big and intense/tight.

Notice he says "the entire sky was full of these spirals". This is strong evidence that the Moscow spiral was simply a twisted contrail like these, but viewed from end on, so it looked vertical.

 

[Mick West]

It's probably worth to note that Moscow has remarkably cold weather at the moment.

Which might be allowing contrails to form lower, in regions of air that are more prone to this type of rolling advection. Which would explain why you don't see it very often, as contrails typically form higher in more stable air.

 

[Mick West]

Here's a similar things in the US:

http://www2.nbc4i.com/ugc/snap/weather/helix-cloud-over-columbus/8429/

Posted by:PSchulzLocation: North 4th Street and 18th Ave
Category: Weather
Interesting cloud my daughter noticed all alone in the sky Sunday morning about 8:55 am 1/29/12.

A comment on the above suggests it's not a contrail:

George LittleYesterday 11:10 PM
Sorry, it's not a barrel roll... I'm a Storm Spotter for the National Weather Service and I studied Physics and Meteorology in college. Helical clouds are a fairly common phenomenon. It's basically like a Dust Devil, but the updraft is in the upper atmosphere. The vertical column of air starts rotating fast enough for moisture to condense. You can Google "Helical Vertical Cloud" and find a few images -- I found this one...

http://www2.nbc4i.com/ugc/snap/weather/helix-cloud-over-columbus/8429/

I'm not convinced though. The Kyiv (Kiev) photos above are clearly contrails, and when viewed end on would clearly look like the Columbus photos and the Moscow photos.

 

[Mick West]

Then there's this
http://www.fotothing.com/bigtallgeezer/photo/21a5d311f86948f9b7824f49a386701a/

The photographer claims it's not a contrail, but I'm pretty sure it is. It's a very similar perspective to the 2010 "Mystery Missile" contrail, which also seemed to have a bit of a twist:

http://contrailscience.com/los-angeles-missile-contrail-explained-in-pictures/

 

[Trailspotter]

These photos are from Zelenograd, a stand-alone district some 20 miles NW from the centre of Moscow. All four viewpoints are within one mile from each other. [EDIT actually, it is about 2.3 miles between the most distant #3 and #4 (see below).] Unfortunately, Zelenograd is not on Google StreetView, so I could not locate the exact viewpoints and view directions. I've asked friends in Moscow for more information on this phenomenon, but got no replies yet.

 

[Mick West]

This example of a helix cloud might provide some clues as to formation:

http://www.flickr.com/photos/captured_echoes/5409059139/
Jan 31 2011

Again a winter cloud, so cold weather, possible lower altitude. It looks like cirrus uncinus clouds formed from a contrail, and then twisted. The interesting thing is how the "body" of the cirrus uncinus clouds seems to switch sides of the helix. You would really need to see this cloud in 3D to figure out exactly what is going on here, but consider the initial formation, the fallstreaks (virga), and the twist did not all happen at the same time.

 

[Trailspotter]

In Google Earth, there are some 3D buildings in Zelenograd. I've located the viewpoint and direction of photo #4, the camera points toward the Sheremet'evo airport (SVO):



55.992316733° N 37.212822455° E

 

[Mick West]

And here's photo #1
View attachment Photo #1.kmz

lat 55.981659° lon 37.175485°

 

[Mick West]

Photo #2 is taken from about 110m (360 feet) North of photo #1. Both photos sem to be facing about due east. The large amount of parallax motion relative to the building that is in both shots would seem to indicate that it's a long way off. Hard to say exactly, but at least 10 miles, and probably more like 50-100

 

[Trailspotter]

And here's photo #1

Yes, it is. I also have located all four viewpoints:


and fit photos #1 and #2



There are no 3D buildings for photo #3, but the estimated viewing direction is approximately the same for all four viewpoints, toward the top of the first image.

 

[Mick West]

Some more images from:
http://pikabu.ru/story/prodolzhayu_...hnyikh_yavleniyakh_na_nebe_yetoy_zimoy_896859

 

[Trailspotter]

Here is another photo, not a crop out, from the same viewpoint as #4 (from http://earth-chronicles.ru/news/1-0-13):

 

[Mick West]

Thanks. Here's that image zoomed a bit and contrast enhanced to show the structure a bit better:

 

[Trailspotter]

Some more images from:
http://pikabu.ru/story/prodolzhayu_...hnyikh_yavleniyakh_na_nebe_yetoy_zimoy_896859

BTW, according to the comments on that site, the person on the second photo (#6) is the author of the first one (#5). That is, both pictures appear to be taken at about the same time from the viewpoints just a few feet apart! I'll try to locate these viewpoints tomorrow morning to do some geometry.

 

[Mick West]

And here I've matched both those two photos by scaling them so the building matches exactly (within a pixel, see the fringe), which shows how the trail moved over time

This type of leaning drift is typical of a horizontal contrail near the horizon.

 

[Trailspotter]

I have located the viewpoint of photos #5 and 6:

56° 0'51.39"N 37°11'20.79"E

Here is fit of #5 to a 3D building and the Sun:



I also have modeled the trail by trial and error; the trail is about 10 miles long and 20 miles away (in the centre point) from Zelenograd, above the Moscow suburb Mytishchi:



The modeled trail fits reasonably well in the previously fitted photos #1, 2 and 4. Here is a fit for #1:

 

[Mick West]

That's excellent! I think that demonstrates very clearly that it's a very long horizontal contrail with a twist that looks odd primarily because of perspective foreshortening. Its like the contrail below, but viewed end on from 20 miles away

 

[Mick West]

What altitude did you put the trail at?

 

[Trailspotter]

What altitude did you put the trail at?

About 8 km. I thought it might be a bit lower than usual due to frosty winter temperatures on the ground.

 

[Jay Reynolds]

I'll say magnificent job.

Better still will be to supply a KML file for the trail so that anyone can view this in Google Earth to verify the fit from any point and from all photos.

 

[Mick West]

I'll say magnificent job.

Better still will be to supply a KML file for the trail so that anyone can view this in Google Earth to verify the fit from any point and from all photos.

If you want to do that, you'll need to direct link the photos to web based version not local versions. All six photos above have direct URLs

http://contrailscience.com/skitch/Kryukovskaya_Pier-20121228-090434.jpg
http://contrailscience.com/skitch/Solar_alley-20121228-090613.jpg
http://contrailscience.com/skitch/3_the_20th_district-20121228-090703.jpg
http://contrailscience.com/skitch/4_Savelkinsky_fare-20121228-090839.jpg
http://contrailscience.com/skitch/skitched-20121228-135553.jpg
http://contrailscience.com/skitch/skitched-14-20121228-135931.jpg

Then you can make a folder and move or copy the photos, trail polygon, and position markers in. Then on the folder "Save Place As" ... and save a KML or KMZ file.

You can actually make a KMZ with the images included. I've never done this though:
https://developers.google.com/kml/documentation/kmzarchives

 

[Trailspotter]

If you want to do that, you'll need to direct link the photos to web based version not local versions.

This caused a minor refitting, as the change of image files restored the default FOV. Here is the KMZ file:


The sunlight is set for photo #5 (12/24/2012 6:40 AM UTC); it could be switched off for the others.

 

[Trailspotter]

I'll say magnificent job.

Better still will be to supply a KML file for the trail so that anyone can view this in Google Earth to verify the fit from any point and from all photos.

The fit itself does not prove that the trail was horizontal, but it proves that the helix cloud was at least 10 miles away in the eastern direction. The areas further east are also densely populated, but there were no reports of unusual sightings in the sky. It is either because of some cloud cover, or because the trail looked quite ordinary at a closer view. I'm still searching in russian sources for photos of a relevant patch of the sky taken in these areas on that morning, but so far without success.

However, there is a strong evidence, that it was a horizontal rather than vertical trail. All these photos are made in the morning in the eastern direction, that is, toward the rising Sun. The later found photo #5 confirmed this directly. Yet in all photos, the helix appears to be illuminated from the front rather than backlit, like the buildings below. This is exactly how a horisontal trail would look from the end if it were illuminated from the bottom by a low winter Sun.

 

[Mick West]

The very even lighting would also tend to indicate it is horizontal. A vertical trail would have differences in lighting conditions between top and bottom.

Vertical trails of any size also do not sheer evenly. The movement of the trail between #4 and #7 (in post 15 above), would be impossible with a vertical trail. It's basically an affine transform (preserving any straight lines within the structure), which you can only get if you are looking at a horizontal trail from an angle and it shifts sideways.

 

[Mick West]

Some related images from the Reddit thread:
http://www.reddit.com/r/pics/comments/15eu7o/spiral_cloud_near_moscow_last_morning/

–]alemand 3 points 4 days ago
Another angle: http://imgur.com/bZKzV

ashreturn 13 points 5 days ago
Took this pic yesterday in NJ. Started out as a standard looking contrail, then started to twist and break up.http://imgur.com/Q4kgw

Ferrofluid 1 point 4 days ago
heres a nice picture of horizontal vortex cloud I took

 

[phoomp]

Awesome analysis of this contrail!

Here's another one from February, 2008 that also supports the twisted contrail conclusion.
http://marcvaldez.blogspot.ca/2008/02/dna-helix-in-sky-twisted-contrail-first.html

 

[Trailspotter]

Some related images from the Reddit thread:
http://www.reddit.com/r/pics/comments/15eu7o/spiral_cloud_near_moscow_last_morning/

–]alemand 3 points 4 days ago
Another angle: http://imgur.com/bZKzV

Photo #8 is apparently taken at the airport Sheremetyevo (SVO), halfway between Zelenograd and the location of my modeled contrail and in the same viewing direction.

 

[Mick West]

Photo #8 is apparently taken at the airport Sheremetyevo (SVO), halfway between Zelenograd and the location of my modeled contrail and in the same viewing direction.

Agreed. And I'm thinking this means the trail is further away than you have it, and probably higher. It's a bit hard to tell with the single line you were using. Try an Image overlay:
View attachment Helix Image Overlay.kml

uses this linked image:

Stretched out better.

But still needs fiddling

 

[Trailspotter]

Agreed. And I'm thinking this means the trail is further away than you have it, and probably higher.
...
But still needs fiddling

Well, my initial fitting was just to find an approximate area, above which this trail was residing. It is hardly possible to refine it further without knowing EXIF data of the photos, or without more photos of the trail taken from a wider area.

For example, I have refitted #5 from a new viewpoint a few metres closer to the tower building (where its presumed author stands in #6), using a wider FOV. After that, I have refitted the trail that resulted in its displacement by about 1.5 miles to the North. It has improved the trail fit with #4, but worsen the fits with #1 and 2. But these differences may well be insignificant, because the trail was moving, as follows from the comparison of #4 and 7 above, and all these photos could have been taken at somewhat different times.

As for the new photo #8, it is taken in portrait mode and its bottom edge is level or above horizon. This suggests that the near (top) end of the trail was quite high in the sky (40-45°), or 6-7 miles away (even less, if its altitude was lower than 6 miles).

 

[Mick West]

Yes, the trail is definitely moving, probably to the left (North), although it's hard to say. It would be nice to get the actual time the images were taken. But I think it's all pretty settled anyway.

 

[phoomp]

Impressive job, gentlemen!

 

[Trailspotter]

Yes, the trail is definitely moving, probably to the left (North), although it's hard to say.

There was a light eastern (ENE) wind at the Sheremetyevo airport that morning:

http://rp5.ru/Архив_погоды_в_аэропорту_Шереметьево

It was on the ground, but, it is likely that the high wind direction was generally the same, that is, along the trail and toward the observers in Zelenograd. This could be a reason why the appearance of the trail remained essentially the same; it did not drift far aside but just got stretched as it come closer.

I have located the viewpoint of photo #8 in Sheremetyevo and fitted it in Google Earth:



As the terminal 3D building was offset compared with the aerial photo, I did not use its image for the fit, just aligned the roof level. Instead, I used the three lamposts in front of the terminal, the positions of which are indicated by their shadows in the aerial photo. The trail image overlapped well with my earlier model of this trail without any additional effort from my side.

 

[Trigger Hippie]

Some links to really good images of the same corkscrew phenomenon appearing in what looks like natural cirrus clouds. I'm not sure about copyright so I opted to post the links only.

http://www.ethantweedie.com/category/ethan-tweedie-photography/mauna-kea/

http://jtidwell.net/photos/northern-presis.php?photo=2005-07-11-413-corkscrew-cloud

 

[Ross Marsden]

(slightly off-topic)
I went looking for Kelvin-Helmholz Instability and found this interesting site:
http://www.brockmann-consult.de/CloudStructures/contents.htm

 

[Jay Reynolds]

(slightly off-topic)
I went looking for Kelvin-Helmholz Instability and found this interesting site:
http://www.brockmann-consult.de/CloudStructures/contents.htm

Scott Stevens could have a blast with that site.

 

[GregMc]

There's an interesting satellite pic I noticed on gizmag's "best nasa photos of 2012".
Looks like a helical cloud
http://www.gizmag.com/top-nasa-images-2012/25585/

http://images.gizmag.com/gallery_lrg/nasa2012-7.jpg

In the centre of the image amongst the cloud streets is what resembles a helical cloud viewed from above, but it is also close in appearance to a more familiar Kaman vortex street. http://en.wikipedia.org/wiki/Kármán_vortex_street

Vortex spiral in lee of mountain peak http://www.avonhgpg.co.uk/images/gallery/clouds.jpg

 

[Mick West]

This shows that spiral type structures are not restricted to the lower atmosphere: