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Re: (meteorobs) Re: Fireballs



Bob Lunsford wrote:
 
> I would estimate that 25% or less of all the fireballs I have seen are sporadic.
 
> I would agree this percentage is skewed toward the dates of shower activity. Stating this, I would still venture to say that if one were to view on all nights of the year, half of the fireball activity would still be produced by known showers. 
 
...and Ed Majden wrote:
 
>  Fireball rates are definitely skewed to the dates of shower activity.  See Halliday, Griffin and Blackwell's paper in MAPS 31, 185-217 (1996) "Detailed data for 259 fireballs from the Canadian camera network----".  Table 1 lists the distribution of 754 fireballs by day of the year.  It shows much increased activity in August (Perseids), November (Leonids), December (Geminids)
 
   Thank you, gentlemen. I'm not sure you both took my intent of the word "skewed" the same way. I meant, as Bob interpreted it, that his *observations* might be skewed towards seeing a somewhat higher than representative percentage of fireballs on nights of major showers simply because he would be more likely to be observing on those nights. 
 
    It is clear from both of your comments that many more fireballs do indeed occur on those nights. Without having read the cited article, I would suspect the Canadian camera network data would *not* be skewed as it would presumably have been operational virtually any night, whether a shower was happening or not, making its counts less subject to observer preferences. It would still be skewed by natural factors such as seasonal weather or hours of darkness in summer vs. winter. In either case detailed statistics could be standardized, if one cared to take the trouble, by calculating fireballs per unit Teff on a given date. But you needn't bother on my account; I am happy to accept Bob's and Ed's words as a definitive answer to my question.      
 
    regards, Bruce

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