(meteorobs) Cosmic rays on all-sky cams?

[prospector at znet.com]

Chris,

   Before I joined meteorobs in Jan '99, I observed the night sky for 2.5
years with 10X50 binoculars, often for hours a night almost every night. I
saw many different unexplained light and dark events. Once I saw a light
tree descend with four or five levels, not too bright possibly a +4, but
quite visible with the binoculars. Two other times I saw a dark line end in
perfectly round (as if it were contained in some way) and dim flashes, it
wasn't a point meteor as I saw the path of travel first.
                                        Dave English
                                   Oceanside, California

Quoting Chris Peterson <clp at alumni.caltech.edu>:

> Tom-
>
> I've never seen anything on any of my allsky cameras that I was certain
> was a cosmic ray strike. (BTW, cosmic rays themselves don't normally hit
> CCDs; what happens is that a cosmic ray either strikes a molecule in the
> atmosphere, or one in your camera or telescope structure, which produces
> a secondary spray of particles. These are what normally produce cosmic
> ray artifacts on CCD sensors.) I do see cosmic ray artifacts all the
> time on my regular long-exposure CCD images, and I see the gradual pixel
> degradation that Sony HAD sensors experience over time as the result of
> cosmic rays. So I know they are hitting. The most common unexplained
> phenomenon I record is a single saturated pixel. That is consistent with
> a head-on particle strike, but I doubt that's the cause, since I've
> never recorded the sort of ragged multiple pixel artifact that is more
> typical of cosmic ray hits.
>
> My assumption as to the reason I never see any cosmic rays is that the
> detection scheme used by Metrec (which runs on all my cameras) is simply
> not sensitive to the sort of single frame "flash" that a cosmic ray will
> produce.
>
> Chris
>
> *******************************
> Chris L Peterson
> Cloudbait Observatory
> http://www.cloudbait.com
>
> On 8/23/2011 9:47 AM, Thomas Ashcraft wrote:
> > I am wondering if anyone has any video specimens of a cosmic ray
> capture
> > on an all-sky camera.
> >
> > I have never looked into cosmic rays but I hear they show up sometimes
> > on meteor camera sensors.
> >
> > Thanks for any info on this.
> >
> > Thomas Ashcraft in New Mexico
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