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(meteorobs) Leonid Update for Maltese Observers

Dear Maltese Meteor Observers.

Meteor Astronomy can play many tricks. Clouds, Moonlight, false alarms
are the ones we are most used to. This year's Leonid display pulled a
different one on us all. It is a clear lesson on the value of
predictions and on how one must be prepared... always.

There is the good news and the bad news. The good news is that, from the
hundreds of e-mail reports I have scanned this evening, there was NO
LEONID STORM display this year. So you did not miss anything.

The bad news is that there was nevertheless a spectacular leonid meteor
display this year, with peaks of about 4-5 meteors per minute. The sad
twist is that this rate was achieved at about 4-5 U.T. on Tuesday,
November 17th, some 15hours prior to the announced time of maximum!!

Perhaps we will be doubly lucky next year: A proper storm with the
meteor observing community properly prepared for anything!!!

I attach copy of message sent by Joseph Zammit, who was at Delimara
yesterday hoping for a storm, along with some 30 other persons...:

I am kindly asking Stephen Brincat to circulate this nmesage on his
electronic list.
Regards
Dr Godfrey Baldacchino
Director, Meteor Group

Subject:
        Leonid report
   Date:
        Wed, 18 Nov 1998 14:33:23 +0100
   From:
        JOSEPH ZAMMIT <jzam002@umdot edu.mt>
     To:
        gbal@umdot edu.mt, martingd@maltanetdot net, sbrincat@orbitdot net.mt




The Leonid ‘storm’ - another letdown

At the time of writing, Wednesday 10am, I still do not know what has
happened around the rest of the world, but I assume from what we
observed, and due to the high rates experienced the previous night, that

the predictions were quite late.

A group of some 25-30 persons met in the south, beyond the power
station.  The first determined observers were myself - ZAMJO, FORMI and
GALMA who decided they HAD to be there as soon as the sky was dark, and
we arrived on site at 18.20 LT.  Random observations until we started
the real watch contributed only one possible Leonid and two sporadics to

myself.

I started my official watch at 20.10 LT, because we had to let the
newcomers settle down.  By 23.00, most of the observers had gone away,
and only the original three and PACAL were left to survive.  Fortunately

around 6 friends of Martin came to keep us company for some 2 hours.

Exactly after the stroke of midnight, Leo decided he should not let us
down to the full, and a savage super extra long hyper fast Leonid sprang

forth and blazed through at least 50? of the heavens (the building
behind our backs obscured the rest of it).  Soon after came the best of
what Leo had to offer last night - with 7 good meteors in 20 minutes.
The Leonids seemed to be following a cycle.  There would be an
‘outburst’ of about 10 to 15 minutes - with Leonids approx. every 2 or 3

minutes, then 20 minutes of complete silence.  What we must have been
witnessing were the last few fragments as the Earth moved out of the
Leonid stream.  The Leonids we observed were almost all ‘typical’ - very

fast, relatively long, 1 to 2 sec persistent path and some terminal
flares.  The Taurids were slower, shorter and less bright on average.
However, they had more common terminal flares.  Most notable were two
Taurids which had a double terminal flare - they flared up, their
magnitude dropped, then they flared up again.  One of them had quite a
notable greenish tinge also noticed by GALMA.

Below is the analysis of my observations:
Sporadics
9.45        9.59         1
10.00      10.59        2
11.00      11.59        2
12.00       0.59         3
1.00         1.59         3
2.00         2.45         0
Total                        11

Magnitude Distribution
-1     0     1     2     3     4
  1     1     2     0     5     2

Taurids
9.45       9.59       2
10.00     10.59     5
11.00     11.59     6
12.00     0.59       5
1.00       1.59       6
2.00        2.45      2
Total                    26

Magnitude Distribution
-2     -1     0     1     2     3     4
 1       2     1     3     7     8     4

N.B. I have on purpose excluded the observations of Sporadics and
Taurids from 8.10 to 9.45 due to the fact that until then I had marked
Taurid meteors as sporadics, not knowing that the Taurids were active.
In fact, I we analyse the sporadics observed until then, i.e. 14, this
is not comparable with the sporadic rate of only 2 or 3 per hour we saw
later on, but if we put in the Taurid rate of 5 or 6 visible per hour,
it is plausible enough to assume that about 10 of them were in fact
Taurids.

Leonids
9.00       9.59     1
12.00     12.59    16
1.00       1.59     10
2.00        2.45     9
Total                   36

Magnitude Distribution
-4     -3     -2     -1     0     1     2     3     4
  1      0      4      5      5     11    3    3     4

With regards to SLM, as we did not have observing maps, we could only
crudely estimate it.  At the beginning of the watch, it was only about 5

to 5.5, depending on the area observed.  This crept up to about 5.5 to 6

at the most after midnight.  After 1.55 the SLM suddenly dropped to the
range 3.5 to 4.5 due to quite hazy conditions.

Obscuration also played its part.  From 00.30 - 1.55 we experienced
about 20-25% of cloud cover.  From 1.55 to 2.25 it was about 40%, and
during the rest of the watch it rose to around 70%.  Still, with such
conditions during the last three quarters of an hour I observed nine
Leonid events.

Though there were three other observers who stayed there, only GALMA
observed all the way through those long 6 ½ hours with me, and his
observations were quite in the same lines as mine.  The others decided
it would be wiser to take a nap every now and then.



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