My Leonid Night
Well, well, well... This year I had planned it all very carefully: I had
started making video recordings with an image-intensified camcorder two
weeks in advance, fine-tuning everything, calculating trade-offs between
field of view and limiting magnitude for the video, getting equipped with
extra batteries, tripod, etc., and of course training myself with the
weak but interesting taurid shower, on during all of early November:
seven nights of observation, for a total of about 12 hours, had provided
68 meteors, 38 of whose were in fact taurids, plus some early leonid
(on the 12th and 13th of November) and many sporadic meteors.
Everything seems in order, reclining chair and warm throw included,
when the unexpected happens: I need to fly to Italy
with my wife and child a week before planned. When ? We need to be there
on the 19th, fair and square. I struggle hopelessly with Lufthansa, the
carrier of my choice, but have to resign to flying out on the afternoon
of the 17th: that means leaving Chicago at 2.40 pm, landing in Frankfurt
at 6am the following morning!
Needless to say, I'm scorned, and accept the defeat as the unavoidable fate
of the caring husband that finds his normal occupations upset by the more
urgent and important needs of his family members... Oh well, I think to
myself: the shower is predicted to be bad as seen from Chicago, where I
would be otherwise, and in no way can I make it to observe the peak from
the more promising sites in Europe... I end up forgetting about the whole
thing, wishing to myself to read on the Nov 19th newspapers somebody say,
"Oh, this year was not the one, but November 2000 will for sure be great!".
The United Airlines-operated flight to Frankfurt is almost fully booked,
and we are happy to get three central seats, with one free seat for my
eight-months old baby. I look at a movie, eat a little, and then, at 7.40
of my wristwatch, I remember something. "Hey, wasn't this the time predicted
for the leonid storm", I tell to myself.
"Well, all the window seats are taken, but let's
go to the big door and have a peek outside... Who knows, maybe some meteor
will show up..."
I reach for the slim window on the big door of the B777, and press my nose
to the plastic window. Whizzz! The very moment I focus on
the night sky, I see a leonid meteor!! It takes me a second to realize that
the radiant must be barely off the horizon. The meteor seemed in fact
to come out of the ground, flying parallel to it, if not upward.
I can see all of the
big deeper, plus some stars of draco. I am startled. What is the ZHR, I think,
if I see a meteor the moment I peek at the sky, with eyes unaccustomed to
darkness and the radians at zero degrees, with a double window in front of
me and moisture over it to boot ?
I of course decide to investigate it a bit further, and whizz, here come
more! I grow excited, as
I start seeing meteors at increasing rates. Some seem to dip below
the plane! I see a bright red meteor, then more faint ones, all characteristically fast and with half-second lasting trains.
And the rates grow! In the slim field
of view I can get by making my nose a pancake, pulling the neck upward
and counterbalancing with stretched legs that cause trouble to passers-by
and considerable pain to my muscles,
I start seeing two meteors at a time! I emit a cry when I see it the first
time, but then it happens again, and again, and once three meteors cross
my field of view!
In the meantime, as a diligent amateur, I try to keep note of the counts,
knowing that the large uncertainties due to the unknown field-of-view and
uncertain plane position (I'll need a double integral to compute the ZHR,
I reason, since I'm moving diagonally in direction SE as the radiant is
rising) will make my counts less precise but still useful. The limiting
magnitude is excellent, though: I estimate a clear 6.0, all the way to the
horizon. It pays being airborne!
The counts: 70 is the final number between 1.45 TU (7.45 on my watch)
and 2.00 TU, and 93 between 2.00
and 2.15 TU! I have never seen so many meteors in a single night (my
former record being 80 in a four-hour perseid stand in 1990), and I've
only observed for 30 minutes, with a field of view of probably less than
a half of what I can get to with my eyesight, with a radiant that's
just above the horizon now! Unbelievable! I mentally compute a
very rough estimate of the
ZHR: 93x4 is 372 per hour, times 2.5 for the field of view, times 1.5 for
the limiting magnitude, times probably about 2 for the height of the
radiant: 2800 !!!
A small tremor shakes the plane. It does not bother me, but soon a
flight attendant taps my
shoulder: "You need to go back to your sit, sir, the fasten seat belt
sign has been turned on". Damn. I nod, and disappear in the washroom,
only to come out as soon as he's turned his back. I go back to my very
uncomfortable position, but the buddy is back too: "You need to go to your
seat, sir". "You don't understand, there's a major meteor shower on right
now and I won't miss the chance for anything in the world!" I reply, with no
success: the guy is pretty stubborn. Then an idea:
"Ok, here's the deal. You find me a window seat and I'll sit down and give
you no more worries." He says he can't do that right now, and adds he's
going to call the captain. "Very good" I say, "call the darn captain,
I'm tired of talking to you". Rude, but I'm really pissed by the
I turn back to the stars, and it's my wife's turn. The baby's been crying
and she needs me. I try to explain her the exceptionality of the situation,
but have to resign to the force of events.
Damn. I miss fifteen minutes this way, and can only run back to my place
at 2.30 TU. The rate has diminished, but is still a steady 64 in the
next 15 minutes. I feel I have to go back to the baby, my wife is furious of
my running away... In the meantime I reason that the peak must have happened
already: 64 is almost 4 sigmas below 93, while the radiant has been rising (at
almost twice the normal speed, due to the plane motion), so the rate must
have been decreasing, that's for sure. Too bad, but I've already seen
227 leonids plus two sporadics to boot (one is actually a taurid).
In the two following hours I'm able to total four more 15-minute counts
and a 5-minute one,
when the rate decreases to 30-40 per 15' but keeps alive (still 15 in the
last five minutes!).
At 4.25 TU the sky starts to lighten, and we need to
prepare for an early landing in Frankfurt... The plane sinks in a deep
layer of clouds, while I scribble with a pencil on a paper towel my last
rates. I've totaled 405 meteors, 400 leonids in 1 hour and 50 minutes.
Back in Venice, at last. Hmmm, cloudy. A call to Enrico Stomeo confirms
my first impression: almost nobody was able to observe from Italy, Germany
or France! In Spain they are reporting rates of the order of 2000/hr...
The peak appears to have been shortly after 2 UT, and I recall that I saw three
meteors in a split second just at that time. Wonderful night! And I have
to reckon with a fact: in the US they saw only rates of about 50 per hour,
and in Italy they saw nothing... Airborne was the best bet for me: I couldn't
have been luckier that night!
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Last modified: Sun Dec 12 14:46:39 CST 1999