(meteorobs) Probable cosmic ray and not a meteor

[Thomas Ashcraft]

On 11/20/11 6:49 AM, Jean-L. RAULT wrote:
> Dear Thomas
>
> What is (are) your argument(s) in favor of a cosmic ray ?
> Considering the duration of the visible trace and the apparent size of
> the Moon (0.5 degree), it could also be compatible with a faint meteor
> trace.
>
> Jean-Louis


Hi Jean-Louis,

My argument for cosmic rays in this case would be the description of 
cosmic rays on CCD sensors in a message by Pete Gural to the meteorobs 
list on August 23, 2011:

::::::::
"Cosmic rays can generate various length streaks across today's 
sensitive CCDs. The length varies according to the incident angle of the 
cosmic ray relative to the normal of the focal plane. That is if the 
cosmic ray hit perpendicular to the CCD face, then the pixels lit up 
would be a short segment or even a single pixel. While if the cosmic ray 
came in at a shallow grazing angle to the focal plane, then a long 
linear streak would be seen. They tend to be jagged, the same way that a 
line drawn on a pixilated grid makes a stair-step sort of appearance 
(loosely speaking). They also only tend to last a single frame, thus 
making it possible to distinguish between meteors by the latter's 
persistent movement across several frames. Cosmic ray tracks also do NOT 
show the point spread function (smearing of light across several pixels 
due to the optics) that stars or meteors produce.

A few years ago I ran a detection algorithm on a cover closed, dark 
enshrouded PC164 camera, and found about 2 cosmic rays per night. 
Today's Watec 902H2 Ultimate is more sensitive and may have more hits 
per night but I have not tested this.    Cheers... Pete Gural"
::::::::::

In my video the main streak is contained on one single video frame and 
is jagged.  Also a meteor would take some frames (time) to travel that 
many pixels across the sensor.

But I do not know much about the subject and am just learning.

Thomas



Le 20/11/2011 01:44, Thomas Ashcraft a écrit :
>> This is nearly off-topic but since it looks somewhat meteor-like and was
>> captured on my meteor arrays I am posting this observation.
>>
>> While processing a Leonid meteor capture on my all-sky video I think I
>> detected three cosmic rays on a single frame of 30fps video.
>> Interestingly, there may also be extremely faint VHF sound with this
>> cosmic ray incident. (Barely audible.)
>>
>> 1 MB .mp4 movie
>> http://www.heliotown.com/PossibleCosmicRays_Ashcraft.mp4
>>
>> 200 KB .gif animation ( no sound)
>> http://www.heliotown.com/anomalyNov182011_0836ut.10.gif
>>
>> Thomas Ashcraft - New Mexico
>>
>

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