(meteorobs) Determining physical dimensions of a large fireball in the sky?

[Pat]

With a single video capture you can't do much with it. You might be able to get velocity if you have some other verbal sighting tracks...but mostly you get velocity relative to the camera. With two or more videos you can get absolute velocity and some ideas of size. Since you can get deceleration versus altitude with two or more videos you can get estimates of size. If you recover material and get composition then you can tell even more. There is a paper by Ceplecha in the BAIC volume 48 page 222 called "Geometric, Dynamic, Orbital data...from Fireball Networks". It is available on the NASA ADS system. You might read it. They have a software program called FIRBAL that does the numbers for them from calibrated cameras. One of these days I am going to make an Excel Spreadsheet that given the azimuth and elevation from 2 locations will calculate the trajectory and landing locations. I have it now for a simplified (linear path, constant velocity) solution, but working on getting a more general solution. I will put it in the files section if I ever get around to finishing it.

--- In meteorobs at yahoogroups.com, Thomas Ashcraft <ashcraft at ...> wrote:
>
> Here's another question for this forum:
> 
> Can the actual physical dimensions of a fireball in the sky be 
> determined with accuracy from video captures? I am not referring to 
> brightness magnitude in this question but rather to the dimensions of 
> the meteoroid/meteor itself before and during its burn.
> .
> Thomas Ashcraft
> 
> 
> 
> 
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