[meteorite-list] Smoke Trail

Chris Peterson clp at alumni.caltech.edu
Wed Sep 13 23:42:49 EDT 2006


It was Darwin harbor. http://www.cloudbait.com/science/darwin.html

Contrail shadows occasionally are projected onto underlying clouds, but 
most often occur when the contrail, sun, and viewer are nearly in line. 
In that configuration, the viewer is actually seeing a plane of darkened 
air, viewed edge on. It is seen in contrast to the forward scatter from 
the surrounding unshadowed air. A striking example is seen here: 
http://www.cloudbait.com/gallery/gallery_sky.html .

Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com


----- Original Message ----- 
From: "Sterling K. Webb" <sterling_k_webb at sbcglobal.net>
To: "Mike Groetz" <mpg444 at yahoo.com>; "G. Nicula" 
<treasurehunter at chartermi.net>; <meteorite-list at meteoritecentral.com>
Sent: Wednesday, September 13, 2006 7:07 PM
Subject: Re: [meteorite-list] Smoke Trail


> Hi,
>
>    Although I can't pinpoint the date, there was
> a set of photos (interval-timed) from Australia
> of Sydney (?) harbor. One frame showed what
> appeared to be a streak from the sky striking a
> lamp post on a pier. Was it a meteorite? (The
> lamp was blown up.)
>    One of the astronomical forums hosted a huge
> discussion of the photo, analysis, frame differences,
> blah, blah.  Some thought it was a photo of a bug
> close to the camera, some thought ball lightening,
> some thought the "trail" was the shadow of a
> contrail (the photo was taken at twilight sunset),
> and the guy that suggested this posted a number
> of photos of the shadows of contrails. I didn't
> think this photo in question was explained as a
> contrail shadow (calculated the sun angle and the
> "shadow" angle was different).
>    But there is no doubt that there IS such a thing
> as a shadow from a contrail. When I Google
> "contrail shadow" I get lots and lots of stuff:
> http://www.google.com/search?hl=en&lr=&safe=off&q=contrail+shadow
>    Even better, Google Images for "contrail shadow":
> http://images.google.com/images?hl=en&lr=&safe=off&q=contrail%20shadow&sa=N&tab=wi
>    Are any of these resemble what you saw, George?
>    And, yes, a fireball trail could produce a
> "fireball shadow," I suppose. It's just that fireballs
> are a lot rarer than jets! Even a 737 or 747 is hardly
> visible as an object at eight miles high (12 miles
> away at an angle); military jets are even smaller
> (and higher and faster).
>
> Sterling K. Webb
> 




More information about the Meteorite-list mailing list