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(meteorobs) Re:meteor notes

1996 June 8

     There were 58 messages here in 2 days.  Looks like growth of this
network hasn't topped out yet.  For satellite images of weather try a
webcrawler search using keywords goes-8 and image.  Very good pictures are
found at MIls: current weather ...  Localized weather discussion on TV here
is quite good.  Tropical weather has sharp variations over short distances
especially with heavy showers, so mention of small cloud groups over land or
water is important.  In hurricane season they watch all the surrounding
bodies of water closely.  But what irks me is the slant toward beachgoers:
any hint of rain brings out long faces and negative remarks from TV
weathermen.  This was true throughout my early years in Miami.  I asked Joan
how they handle it in Chicago, her native city; she said they give neutral
forecasts without any editorializing about what constitutes a "nice day."
We have to be seriously dry before anyone on TV admits we need some rain,
like right now.  Nothing in two full weeks, and with the sun passing
overhead everything is shrivelling up. 
     Nights have been reasonably clear for some time.  I'm free at last to
get back to observing: Joan's last workday just went by.  But we're going to
north Florida next weekend, then Alaska early July, then Chicago during the
Olympic period.  So observing will have to fit around that.
     I have not seen any meteor turn dark while crossing the Milky Way.
Black meteors crossing it do look enhanced, and I don't have them in any
particular orientation within my field of view.  Almost all of them are
sporadic.
     Cheap tape recorders these days are junk.  My first recorder from 1972
was good--it lasted until 1987.  The next one, from Radio Shack, went about
5 years, reasonable.  But the following one went bad after just one year--OK
to play tapes but unreliable for recording.  I got yet another RS, defective
right from the start.  So I located a used heavy-duty recorder, even that
I'm concerned about how it will perform outdoors.  All recorders slow down
in temps cooler than 60F, they must be kept warm somehow.
     Nights are mostly comfortable around here, although summers can be a
bit too warm.  I have over half my nights at 70F or higher, maybe a quarter
more in the 60's, and the rest in the 50's and some 40's.  Something good
has to be going on for me to observe in 30's, which are only a few nights in
a year anyway.  Comfortable refers to temps only.  Once the wet season gets
underway mosquitoes get to be rather bad.  I find burning coils works fairly
well.
     The best site I have experienced was on the old Bahia Honda bridge in
the Keys, 50 feet above the water and free of bugs, combined with a black
tropical sky.  This all ended in the early 80's when the bridge end segments
were removed to stop access, piles of rock put on the approach, and growth
of Big Pine Key ruining the sky.  Bill Gates found it a novelty to observe
in his running shorts instead of bundling up against cold.  LM7.5 was
routine there; I once got 7.7.
     No workup of data from fabricated radiants has been done yet.  A
cursory look soon after we started this showed that Mark Adams was
consistently recording twice as many FR meteors as I was.  We agreed on the
rules to use yet got different results.  Since 1982 I have been accumulating
this data for an eventual study.
     Fireflies are in the Everglades all year.  There are very few towards
Fort Myers.  In Miami we had click beetles, which are not true fireflies.
These critters have two headlights instead of one taillight, and they would
glow continuously for a minute or more at a time.  They are fun to catch and
put in a bottle.  While observing I find that a firefly's color (YG) is
suspicious, and it almost always gives itself away by flashing a second time
further along the route it is taking.
     My observing site is on a paved cul-de-sac in the SE corner of Lehigh
Acres.  Florida has many square miles of undeveloped residential roads.  The
present site was created only a few years ago with smooth asphalt.  It is
clean and I don't even need a ground cloth.  Some weeds recently made an
appearance; I carried a shovel last time out and scraped these off to avoid
damaging the surface any further.  I haven't seen a snake there yet,
although diamondbacks are common in more wooded parts of Lehigh especially
around palmetto thickets.
     Satellite color is like reflected sunlight, pale yellow.  Airplane
lights have various intense colors.  I have a 12.5" f/4 reflector with an
eyepiece that gives an undistorted 3-degree field of view.  A couple of
times an hour something in orbit goes through, as faint as 13m.  Must be
paperclips or other very small objects.
     Nebulous meteors are interesting.  The first one I saw looked like a
globular cluster seen unresolved in a 2.4".  More common are meteors with
nebulous envelopes around a bright head.  Another odd type looks like a
moving train-like streak, often sparkly orange.  My last time out had 2 Tau
Herculids; one fit this last description at 2m.  Taus are not on the IMO
list either, but their very distinctive appearance and slow speed makes them
real.  I actually saw 2 the first hour, then no more.
     If the IMO does local hours automatically, then why not be sure you
have started just before one of these hours starts?  Or end right after one
ends?  Get more local hours completed for the time you are out there.  This
is what I have always done.
     I saw the 1969 June Lyrids from Mississippi June 15 with no warning
that anything unusual would happen.  It was amazing to see 5 in one hour
come from Vega.  I had forgotten that they are fairly slow.  In 1972 and
1975 I saw essentially nothing.  But Hindley of the BAA had applied "careful
corrections" to low observed rates and inflated it into a new major shower.
His original paper showed an average correction factor of 6.  Then S&T
picked it up as a regular major shower for the bulk of the 70's.  Any
beginner seeing this would feel compelled to "confirm" the June Lyrids since
it was in print.  I know this happened in Florida; one young observer had JL
rates similar to my total rates in 1975.  He must have called everything he
saw a JL.  I finally wrote S&T about this, and they dropped it.  It would be
best to keep June Lyrids on the back burner until they reemerge.  The
largest correction factor I can handle is 1.5.  You are sticking your neck
out with anything larger as far as uncertainty goes.  To take a low rate
from poor conditions and multiply it by 4 and more is preposterous.  The
result is unreliable and usually unrealistic.
     Theta Ophiuchids are distinctively slow but not numerous.  I have seen
rates of 1-2/hr a few times.  The Day Arietid radiant is 12 degrees up at
dawn here.  I would not think a sporadic chance lineup is very likely with
this one.  Path length would be obviously very long as well as coming from
ENE.  I have several of these in my lifetime.
     It may be time to discontinue my written newsletters and just do them
here.  Almost everyone is now on line.  I still have to do a Geminid report;
various events here have kept me from it so far.

Norman McLeod

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