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(meteorobs) Leonid Summary

I hope I am not duplicating the efforts of Joe Rao or anyone else here, but
I have posted a temporary summary of the Leonids, based primarily on time
zone. The summary is based on over 600 observations posted on meteorobs as
well as my own e-mail. For those that may not know, even more details
covering the beginning of the outburst are included on my site at

http://medicine.wustldot edu/~kronkg/leonidresults.html

The summary of the Canary Island observations, as well as those across
North America and back into Asia are as follows.


Report #1: The Canary Islands (the place to have been)

       Reports from the Canary Islands (Spain) have been received from two
individuals. Francisco A. Rodriguez Ramirez indications that the meteors
were continuing to increase in number from what observers on the European
continent had reported. At times it became difficult to count the meteors
because several would fall within a couple of seconds. He said his
colleagues Maximum Suýrez and Fracisco Rodr'guez were making counts in
10-minute intervals and at one point detected 50 within that span of time.
Another observer in the Canary Islands, V'ctor R. Ruiz, reported similar
numbers, with his highest 10-minute counts coming within the hour prior to
twilight. He said that before 5:17 UT his highest 10-minute count had been
43, while after 5:17 UT he had four consecutive 10-minutes counts of 49 and
higher, with the highest being 56. This amounts to over 300 per hour. Ruiz'
breakdown of the brightness of the meteors indicates 24 were at least
magnitude -6.
       Despite these two very consistent reports another second-hand report
exists from the Canary Islands which indicates the display was even more
spectacular. International Astronomical Union Circular 7052 was published
on November 17 and acknowledged the Leonid maximum came many hours earlier
than expected. Daniel W. E. Green says, "A. Fitzsimmons reports that a
group of observers at La Palma observed about 1000 Leonids/hr around Nov.
17.15, increasing to about 2000/hr around Nov. 17.19." These dates are
given in Universal Time. Although the LaPalma estimates need to be
confirmed, it is obvious the Leonid rates were over 300 per hour just prior
to the beginning of morning twilight. It is possible rates may have
continued to increase, but with the radiant then over the Atlantic Ocean,
no observations from ships or planes have yet come forth to confirm or deny
this.



                             Report #2: North America and beyond (preliminary)

  (With over 600 reports in hand from around the world, I am working to
produce more detailed reports which I hope to post within the next couple
of days. But for now, here is a rough breakdown of the observations)

       The Canary Islands saw something close to the peak, but the actual
peak may have gone unobserved somewhere over the Atlantic Ocean.
Interestingly, I did receive a report from Brazil a few hours ago (Nov.
19), which only included counts of bright meteors on the 17th. There are
indications that the bright meteor rates may have been only slightly less
than the Canary Island observations. But I am requesting further details.
       By the time the radiant was observed over the East Coast of North
America, rates were off from the Canary Island totals. Observers in Nova
Scotia were detecting rates as high as 164 per hour at one point.
Interestingly, several observers in Delaware, New York, New Jersey,
Maryland, Virginia, South Carolina, and Florida very consistently estimated
rates of 60-70 per hour. There was also a noticable decline in the number
of extremely bright meteors.
       When the radiant reached the midwestern United States, there seemed
to be a further slight decline. My group consistently estimated rates of
50-60 per hour during the middle of our 7 hour watch. Other midwestern
observers obtained similar totals.
       Interestingly, rates seemed to jump again for observers in Oklahoma,
Texas, Utah, and Arizona, where estimates of 120 or more an hour are very
common. By the time California and Oregon came into view, the rates had
again dropped, although the numbers are inconsistent right now. It would
seem rates might have
dipped below 60 per hour.
       The subsequent Asian results are also scattered for the night of
November 17-18. Although one estimate exists indicating an hourly rate of
about 100, most indicate rates of 20-40 per hour. All reports note an lack
of bright meteors as compared to the previous morning.



A note added to this is that I have finally obtained Fitzsimmons'
observations as of this morning and will incorporate them into the Canary
Island scenario later today. The observations across the US are
surprisingly consistent until I get to the west coast for the morning of
the 18th. Any additional light that can be shed on this region would be
much appreciated. Likewise, the subsequent Asian observations are rather
sparse right now with some large inconsistencies.

Gary


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