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From: TerryMosel@aol.com
Date: Thu, 21 Nov 2002 17:26:38 EST
Subject: LEONIDS & Lecture

Hi all,

Sorry I couldn't reply sooner - I was off giving a lecture to NUI Maynooth, 
followed by a visit to LoughCrew. 

Oh well....  We should be used to it by now!  I've had reports from all over 
Ireland of total cloud, so please take this as a reply and thank you to all 
of you who reported thus, rather than replying individually. I even had 
cloudy reports from the NE USA, and from Italy, so we weren't the only one to 
miss out!

But the following report from Andrew Elliott in England shows that David 
Asher & Rob McNaught's predictions were pretty accurate - as we have grown to 
expect!

"I joined members of the Blackpool and District AS (BADAS) at their observing 
site near Pilling on the NW Lancs coast, this morning. Wandering thin cloud 
was present for most of the night but this steadily thinned out giving good 
clear spells in changing directions.  I regret to say none of us were 
"professional" meteor observers so we did not attempt accurate meteor counts. 
 So, apologies for the non-scientific, subjective, nature of this report!  
Also, as you know, owing to my current temporary situation, I was not able to 
carry out any video work although my intensifier system was taken to Spain by 
Steve for use as a nearly-all-sky camera.

Having said that, limiting magnitude for most of the night was 3-4 looking 
away from the moon towards the N/NE.  Meteors were visible from our 01:00 UT 
arrival time rising from an estimated one per 2-3 minutes to about 10 per 
minute at the peak.  There was a preponderance of bright meteors from mag 1 
to -2.2 (Jupiter magnitude) and several brighter fireballs.  Some of the 
brighter ones showed colour - red, green or
blue.  Some were seen in Orion and close to the moon.  There was an 
apparently equal number of fainter meteors down to the limiting magnitude 
although the bright moonlight could have hidden many more.

There was marked evidence of clustering or "clumpiness" as reported in 
previous encounters.  In the early stages, there could be 2-3 in quick 
succession followed by a few minutes without one.  Later, there were several 
instances of simultaneous Leonids shooting out from the radiant in all 
directions, and also close pairs of Leonids in similar trajectories.  The 
peak of activity did occur around 04:00, in line with predictions, with peak 
bursts of around one Leonid per second.  The rise and fall in rates around 
the maximum appeared to be symmetrical.  Several sporadics and members of 
other showers were also seen.

With the extreme wind chill cutting to the marrow and suddenly thickening 
cloud, we finished observing at 05:45.  While our observed maximum visual 
rate of about 600/hour may not have been a true "storm", it was still 
exciting and rates could have been much higher in the absence of moonlight 
and thin cloud.

Around 04:30 a large dense cloud had covered the low altitude moon before 
passing away to the west.  During this period, the limiting magnitude 
elsewhere improved markedly (mag 5?).  Given the "local" nature of cloud, the 
"magnitude" of this effect was not expected."


And a final reminder: Don't Forget the Biennial Robinson Lecture on Friday 22 
November, in the Studio Theatre, Market Place, Armagh, at 7.30 p.m. It's by 
Professor Carl Murray (a 'local lad'), University of London, entitled "In 
Search of Our Origins: The Cassini/Huyghens Mission to Saturn". Prof Murray 
is one of the principal investigators on this major mission. 
Admission free, but by ticket only, from  
Aileen McKee, at ambn@arm.ac.uk, or tel 028 (048 from ROI) 3752 2928.

Terry Moseley


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