----- Original Message -----
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. Take away the Perseids and
the Geminids and then the sporadic fireball percentage would rise to near
75. By the way, I would count the year-round antihelion source as shower
activity since it is assigned official names through much of the
year.
Clear Skies!
Bob Lunsford
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).
Ed Majden
Courtenay, B.C.
Canada