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(meteorobs) Re: Aug 13/14 Perseids poor + more

The night of Aug 13/14 years ago was a good one, but more often in recent
years it hasn't been.  Just last year it was surprisingly good, up to 27
Perseids/hour, which equalled my max night rates.  1997 was a letdown with
just 12/hr at best.

rates 1997 Aug 13/14, Norman McLeod

726 - 826 UT    1.00    F1.00    LM7.0     12 PER    1 KCG    3 NDA    2 SDA
1 NIA    4 SPO    23 TOT

826 - 941 UT    1.25    F1.00    LM7.0     12 PER    2 SDA    1 NDA    4 SPO
19 TOT

There were no Alpha Capricornids and no South Iota Aquarids.  I was pleased
with the rather good Aquarid activity.
Sporadic rates were dismal and Perseids unimpressive.  An orange -2m Perseid
with 2-second train was the best of the night, and the next-to-last meteor seen.

I saw one Kappa Cygnid, again.  Radiant size has been moot, for there have
been no suitably slow meteors to screen out on size alone.  Nothing else
slow came from the entire NW quadrant, much less a radiant 20 degrees
across.  All the Kappa Cygnids I have ever seen came right from, or very
close to, the listed radiant location.  On both of these nights, the Kappa
Cyg was the slowest meteor seen.  The radiant is still almost 60 degrees
high at culmination here, so that ought not make any discernable difference
vs. northern observers.  Different rules are being used in different places
on this one shower, for the difference in rates is extraordinary.  This has
been going on for many years, with rates 5/hr in Europe rather common, but
only a couple per night here.

For fast showers, I feel quite liberal using a 4-degree radiant for
screening.  The Perseids come from a tight, under-2-degree radiant ;
especially noticeable when I faced Perseus in the great 1981 shower.

My best two quarter-hour intervals were 326 - 356 EDT, having 21 and 23
Perseids.  This was around the same time Joe Rao saw his increase.  But he
saw as many as I did in sky LM5.5, indicating that his perception is twice
mine.  Is anybody normal any more??  Looks like Cathy still is.  I'm
surprised Bob didn't go well over 100/hr since I had a good year for a change.

I don't have Marco's 1996 Geminid magnitudes; thought he sent these out.
Would be good to compare our magnitude distributions there as well.  Leonids
had a major change in magnitude average between Europe and North America ;
it will not be easy to demonstrate a change for the Perseids with their
broader peak.

Perseid fireball totals are intriguing.  I, too, am in awe at what
transpired over California, but I don't have any data for comparison this
year.  In no past year did I get more than one Perseid of -8m, in fact, that
is as good as I have ever done.  I don't expect to see a good distribution
of fireballs in any given year, as quite a few have had none or just one.
Below is my Perseid magnitude table for the years 1972 to 1981:

-8 : 1
-6 : 2
-5 : 3
-4 : 11
-3 : 13
-2 : 33
-1 : 91
0 : 232
1 : 367
2 : 910
3 : 884
4 : 784
5 : 629
6 : 171
7 : 7

total : 4138

I need to determine whether these are from dark sky only or from everything
lumped together. Dark sky is suspected.

1972 and 1977 are two years with almost no fireballs.

I really hesitate to say whether any enhancement of Perseid rates is still
around.  What happened this year fits with the 4-year cycle evident all of
my observing years.  My best years were 1969, 1977-78, 1981, 1988-89, 1997.
Some of the fourth years failed to contribute their share.  For what it's
worth, S&T reports indicate 1961 was a good year, but I was watching from
Miami.  1965 had a full moon, and I was flying home from summer school that
night from Tallahassee.

Norman