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Re: (meteorobs) Southern Fireball Rates
>I doubt the incidence of fireballs is higher in the southern than the
>northern hemisphere, but that's just an opinion, further investigation is
>needed.
>Tim Cooper
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Tim,
For my location, I've only seen 7 fireballs for the year. Two were Lyrids
and 1 was a Quadrantid. the other 4 were sporadics of( -3)2 and( -4)2
magnitudes. Mighty lean for me so far. My fireball rates for some of the
past years are listed below:
1992 - 51
1993 - 74
1994 - 71
1995 - 54
I'd say right off hand that about at least 60 % are from various major
showers and only a few above the -6 range for each year. The above tally
doesn't paint an accurate picture really. The time frame is missing. I'm
really curious about looking at the sporadic fireball rates. judging from
your rates, they are probably about what I would normally expect...of course
I'm guessing your observing hours...but have a pretty good assumption. You
are seeing what I would expect though....although there will be some
fluctuations...I've seen this in my own observations...but if you ignore the
Fireballs under -6 and from major showers, I'd only have a handful each year
from a lot of observing time. I believe I sight about 1 or 2/year with
magnitudes above -10 for an average. I just went thru some old FIDAC News and
noted that from New Zealand there are 10 separate fireball reports from
different events with magnitudes over -10....nine are magnitude -12 or
higher. New Zealand is a tiny area! I can't explain this without making the
assumptions that magnitudes may be over estimated. If I take all of
Europe(including U.K. and Spain, Italy, Romania, Poland, Croatia, Germany,
Belgium, Netherlands etc. Forgive my lack of understanding what constitutes
"All of Europe" these days) for the same period (1995) and note the fireballs
of -10 magnitude or brighter, I come up with 21 separate fireball events
from the same source. Knowing that this area consists of a lot of
experienced and dedicated observers, I'd expect something near this many.
Plus when you throw in the existence of some well known very major showers
observed from this latitude, it makes sense to have about this many for
Europe. If New Zealand was of comparable size with the same kind of major
shower activity, I'd say their sightings would probably at least triple. Oh
well, just expressing an opinion...my concern is to seek quality
data...perhaps if we talk about this it will help us all to concentrate about
accuracy in all facets of meteor observing? Keep up the good work Tim. later!
George Z.