(meteorobs) Fw: Disintegrating meteor photos

[Bjørn Sørheim]

Well, I understand your point of view much better now, thanks.
Maybe you can post a link to a photo where this definitely is occuring, it would 
strengthen your argument.
Sorry, I'm not able to produce one easily, I don't have the right equipment here.
(And a clear sky a rarity, these days!)
 
Note also this was a 1 degree field, not a few arcseconds, so the necessary jiggling must
have been quite substansial, only the photographer would be able to say if the setup could
have had that much movement in practice. (Actually he says to me that he feels it is quite impossible from his point of view).
 
There is still a problem with your view:
-Why does the star move in _an arc_ in its most steady phase? Wouldn't an altaz mount (as this was) with no movement produce a straight line - at this resolution? Seems like a big problem to me.
 
Bjørn Sørheim


Robert McNaught <rmn at murky.anu.edu.au> wrote:
On Tue, 8 Mar 2005, Bjørn Sørheim wrote:

> McNaughts idea of a star through a shaking telescope got several problems.
> Most important: What is the cloud then?

It is the star moving randomly about the *camera field* due to
telescope/camera vibrations. I've seen this *many* times.

> Hardly coming from the star, no supernova explosion for shure!
> It seems more than 99.9% shure that the cloud is originating or 
> associated with the bright arc. Just look at the point where they 
> intersect! 100% that they are tied to each other.

The brightness of the vibration trailing is directly related to the
speed of motion. Where the motion is slow (the "arc") the trail is
bright. I think you will find the "cloud" is a single "knotted string" 
of rapid star jiggling. Try a simple experiment. Take a photo of a known 
bright star and jiggle the telescope mount. Try exposures with the 
jiggling before or during the exposure. Try light jiggling or heavy 
jiggling. If you want to know the cause of the event, this might just 
give you the answer.

Cheers, Rob---
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