(meteorobs) Nice variety of Fireballs occured.

[meteoreye at comcast.net]

But the description was :

"Ranging from what I call catagory 3 & 4."  
"Catagory 3 means medium brightness and more than 1 second duration." {what is "medium?}
"Catagory 4 means Fainter and 1 second duration." {what is fainter?}

What are categories 1,2,5,6,7?????

Without any definition, these could mean +1 Magnitude or -12 magnitude.



-------------- Original message -------------- 
From: "Chris Peterson" <clp at alumni.caltech.edu> 

> Keep in mind that there's not a lot of value in a precise definition of 
> "fireball". Meteors are meteors, and they range in brightness from 
> nearly invisible to nearly blinding. The valuable measures are apparent 
> magnitude and absolute magnitude, which are rigorously defined (although 
> in the case of meteors, very difficult to measure with much precision 
> given the rapid variation with time). I use the IAU definition and flag 
> meteors as fireballs when their apparent magnitude is brighter than -4. 
> I find that much more useful than a zenith corrected value. But whatever 
> you use, all you are really saying is that the meteor was bright. 
> 
> Chris 
> 
> ***************************************** 
> Chris L Peterson 
> Cloudbait Observatory 
> http://www.cloudbait.com 
> 
> 
> ----- Original Message ----- 
> From: 
> To: "Global Meteor Observing Forum" 
> Sent: Saturday, October 06, 2007 4:12 PM 
> Subject: Re: (meteorobs) Nice variety of Fireballs occured. 
> 
> 
> Thanx, Ed. I didn't know that the AMS had a reference for their 
> definition. 
> It's still a bit imprecise, but would suggest -4 or -5 as a cutoff. 
> 
> Appreciate you help. 
> 
> Wayne 
> 
> --- 
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