Hole in the clouds? What is this?

gordo · Post by **gordo** » Thu Oct 18, 2007 11:12 pm

More photos here:
http://linuxinit.net/site/images/upload ... n_the_sky/

What the heck is this?

geckzilla · Post by **geckzilla** » Thu Oct 18, 2007 11:18 pm

Looks like airplane trails? The first one would be where the plane flew laterally through the layer rather than parallel to it in the second one. I'm no meteorologist though and I'm surprised if it was due to an airplane that the exhaust had that much effect on the surrounding clouds..

gordo · Post by **gordo** » Thu Oct 18, 2007 11:39 pm

I never saw a plane though... I simply saw the hole in the clouds, and then it just seemed to stretch, and then part the sky... The trail of clouds, or smoke, or whatever it is, wasn't by a plane... the clouds formed that way... I watched it happen. It was very very eerie...

rigelan · Post by **rigelan** » Fri Oct 19, 2007 2:28 am

was it strong winds during the picture or a pretty calm day? If the contrails are not from a plane, they must be from temperature differences. And judging that its so uniform, i would guess a calm day.

gordo · Post by **gordo** » Fri Oct 19, 2007 3:05 am

yep, it was a calm day...

geckzilla · Post by **geckzilla** » Fri Oct 19, 2007 4:05 am

I finally remembered where I saw a similar, even more striking photo of this phenomenon... Duh, right here at APOD.

http://antwrp.gsfc.nasa.gov/apod/ap040112.html

JohnD · Post by **JohnD** » Fri Oct 19, 2007 5:31 pm

gordo,
What spledid pics!
The last on your website, in blue (moonlight?) are truely weird.

But could not this be both 'natural' and the result of a passing aeroplane/
The first above appears to have a straight trail along the cloud before it goes through, and the central wisps seem to extend off in the oppoiste direction as if the palne went through the cloud in descent.

The APOD found by geckzilla mentions that jet exhaust can form the partcicles that trigger this phenomenon.

Thnaanks for showing them!
John

toejam · Post by **toejam** » Sat Oct 20, 2007 7:33 pm

geckzilla wrote:I finally remembered where I saw a similar, even more striking photo of this phenomenon... Duh, right here at APOD.

http://antwrp.gsfc.nasa.gov/apod/ap040112.html

Nah.
Obviously aliens. My fellow Vegans. Spaceship AGEV13 I shouldn't wonder. Dummies always blow it, show themselves to local natives.

l3p3r · Post by **l3p3r** » Sun Oct 21, 2007 6:52 am

It looks like (at least, the 'holes' do) there is a region of local sink in those areas, so the dew point altitude (the height at which the cloud forms) is reduced in that location by the downward traveling cold air... I imagine this would happen more on calm days when thermal convection can get itself organised...

that's my guess

GREAT photos by the way, thanks!

adrianxw · Post by **adrianxw** » Sun Oct 21, 2007 7:34 am

It is a Fallstreak Hole. Some more pictures here. If you search the web for "fallstreak hole" you will find lots of info.

craterchains · Post by **craterchains** » Thu Oct 25, 2007 11:01 pm

JohnD wrote:But could not this be both 'natural' and the result of a passing aeroplane/
The first above appears to have a straight trail along the cloud before it goes through, and the central wisps seem to extend off in the oppoiste direction as if the palne went through the cloud in descent.
John

Think of the size that such an craft would have to be John OO00OO0O0O0OOOO000 FOCLMAO

JohnD · Post by **JohnD** » Fri Oct 26, 2007 8:04 am

Don't make your self more ridiculous than you are already, CC.

A single Google Image search for 'contrails' found the pic on this webpage as second hit. It serves as an example of typical contrails, to show how ill thought is your remark.

http://www.scienceblog.org/community/mo ... le&sid=111

The pic clearly shows the wide extent of influence of an aircraft's exhaust. Note that the widest contrails in this pic are the highest, so not exaggerated by perspective, and that they are easily wide enough for the effect noted above.

John

craterchains · Post by **craterchains** » Fri Oct 26, 2007 9:04 am

FOCLMFAO

BMAONE23 · Post by **BMAONE23** » Fri Oct 26, 2007 11:17 pm

craterchains wrote:

FOCLMFAO

CC
I think we need to invest in a seatbelt for your chair you might then not FOC as much but depending on how much time you spend in said chair, a little LMFAO might be necessary