(meteorobs) Long path meteor -spiraling- *Magnified*

[Chris Peterson]

Meteoroids do tumble, although they usually stabilize quickly. But it is 
difficult to imagine what would be required to get spiraling. Obviously, 
the meteoroid can't be spiraling in space. So you need to assume it has 
some peculiar shape that results in aerodynamic effects that lead to 
spiraling, which seems unlikely. Then, you need to assume it will 
maintain that odd shape, even as it is rapidly ablating away. Even more 
unlikely. Finally, you need to consider that in order to be seen 
spiraling with typical cameras and lenses (as opposed to telescopes), 
the physical diameter of the spiral needs to be somewhere between tens 
and hundreds of meters. Given a typical period of a second or less, the 
forces involved are huge- beyond the material strength of most meteoroids.

Given all that, it seems unlikely that spiraling meteoroids exist, or if 
they do, they are extremely rare. (I'm not talking about very tight 
spirals- mm or cm, as you might get from a combination of aerodynamics 
and rotation- although even those must be uncommon, and only spiral 
along a brief section of their path before they stabilize.)

Chris

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

On 12/5/2011 11:30 AM, eric at meteoritesusa.com wrote:
> Just curious...
>
> Almost all of the videos/movies claiming spiraling meteoroids have
> been "explained away" as either equipment malfunction (shaking) and/or
> software issues, and even operator error.
>
> Is there some bias against spiraling meteoroids or something? Why it's
> so hard for people to believe that spiraling/tumbling meteoroids happen?
>
> Regards,
> Eric
>