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(meteorobs) Re: Leonids 17/18 Nov + more
1996 Nov 17/18
Got a partial night in; clouds were rather dominant but I had the final hour
all clear. Leonids looked very dull at first, then not too bad at the end.
2.33 hours observing for 39 meteors: 19 Leonids, 2 North Taurids, 3 Alpha
Monocerotids, 15 sporadics. Best Leonid was a blue -2 in a thin cloud, so
this one has to be set aside from my average. That was 2.22m using 18
Leonids. Last hour Leonids 13. The prior hour was 40% cloudy so is
worthless. Sporadics were better than usual the last hour also: 11 of them.
Sky 7.3 with prominent zodiacal light.
The most interesting meteor may have been a reentry. It came out of the SW
with its midpoint overhead, an intense orange +2m with a nebulous envelope
and 4-degree tail going 60 degrees in 6 seconds! Looked just like a comet
in motion. Reentries are fairly common around here since I'm just south of
the launch site for so many items. I see several each year.
Tim Printy's best Leonid yesterday was one of my best from here also. The
one at 949 UT (I had 948 UT); I didn't see it directly. Was facing south
when my entire field of view, sky and ground, including the periphery,
turned bright blue-green for a half second. Turning around, I saw a
brilliant blue-green train a degree wide ending only 5 degrees high to my
NNW. Realized at that time someone in the Big Bend area of Florida got a
mighty good one. I called it -8 myself. The train only lasted 10 seconds
due to distance and some interference from the edge of the urban light dome
that direction. Tim is a good 250 miles NNW of me. We surely have more
than one in common, will have to compare times later. His perception looks
equal to mine.
Comments on other messages next. Two of them had no names! Let us know who
you are when you write, please. Most of my -5's and brighter were bolides,
multiple bursts near their ends. The burst sites provide the brightest and
longest-lasting train portions. My other -8 had two big bursts, and after 1
minute these spots were all that remained. They were 3 degrees apart and
hung on for 2 more minutes. No fireball had a single terminal flash.
Each hour had a fairly long dead period. Was fooled by the first one,
thinking the big shower had suddenly ended. Each time, though, it came back
with an active period. The one-hour rates showed a remarkably steady
increase: for 5 hours it went 7,21,23,28,39.
There was no increase in fainter Leonids as the hours passed, and each hour
had fireball action. I doubt if desert dust produced orange meteors in
California, for Florida got the orange ones also. Every individual has his
own color perception pattern, so there's nothing wrong with someone not
seeing orange when others did.
Most of our earliest Leonids were low and paralleling the horizon. The long
trains forming a line like that were striking. After several low ones, I
was rooting for something to appear higher up. Low in the sky you are
looking at more air volume than overhead, hence, to a point you see more
meteors low; particularly more bright ones that can overcome the greater
true distance away. You would start losing fainter ones as you lower your
sights too much.
I am doubtful whether Europe was better off than eastern North America.
Rates in Scotland so far are in the mid to high 20's. Marco in the
Netherlands has the highest I've seen: 56 Leonids in just 35 minutes but
also a rip-snorting 34 sporadics in the same time! Looks like Gates-style
perception (3.8X over me), for I had only 6-7/hr sporadics consistently.
Gates would see generally twice my shower rates but 10X my sporadic rates;
Marco has achieved the same thing. GWG in West Virginia did the best in
this time zone: 49 Leonids one hour but again 15-21/hr high sporadics;
perception looks perhaps 50% greater than mine.
Should get to do some more observing tonight; the last 3 hours will be
enough. I saw my first total lunar eclipse 40 years ago this morning, 1956
Nov 17/18 in Miami. The sky was dark back then right over the city, was
around 6.5 in the eclipse going by my memory of the numerous stars that came
out.
Norman
Fort Myers, Florida