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(meteorobs) Observation November 17/18 2001



Here is my (late) verbal report...



For this year's Leonids shower, I had the pleasure to travel with 
another local observer, Michael Vasseur. We were both determined to 
drive as far as was necessary (from Ottawa, Ontario) to an area that 
would have the best chances for clear skies. We originally hoped to 
setup at Manitoulin Island, but we soon realized that we had to 
travel much further if we wanted to maximize our chances for perfect 
weather...

We spent the entire day on Friday Nov 16 driving from Ottawa to 
Cambridge (Ohio). We debated whether it would be a good idea to try 
and find a dark site to start watching for Leonids on the pre-max 
night. We finally decided against it as we were already tired from 
being on the road all day and the sky had cirrus clouds and poor 
transparency. Instead, we were very anxious to find an internet 
connection to check weather updates for the peak night. We found a 
library which graciously let us use their computers for a few 
minutes. An updated CMC weather map showed Ohio to be in a risk area 
with thin clouds or fog predicted for the big night. With this in 
mind, we drove south another few hours until we arrived in 
Parkersburg (West Virginia) by late evening. We finally stopped at a 
motel for a well deserved good night's sleep.

The next morning, we woke up with one of the thickest fog I've ever 
seen. The sky was supposed to be clear but the fog was thick enough 
to block the Sun and visibility was severely affected. Uploading 
weather updates on Michael's laptop computer showed the bad news; fog 
and humidity for the peak night. We also noticed the low pressure 
over Texas was starting to spread north-east. After examining our 
road atlas, we quickly chose a few candidate observing sites. The 
first possibility was North Bend State Park only about 20 minutes 
away from our motel. A quick visit at this site was worth it as we 
found a very nice open field where we could setup, and staff there 
was very helpful. On the other hand we were concerned that we were 
too low in elevation, and might get caught in fog. A quick phone call 
to Wayne Hally in New Jersey confirmed our suspicions that the fog 
might be a problem, and he suggested we try to get as high in 
elevation as we could! (Thanks for the tip Wayne ;-)

We got the show on the road and travelled south-east all afternoon 
until we reached the National Radio Astronomy Observatory in the 
Appalachians. We were hoping that a group would be there to greet us 
or that we'd at least get permission to setup there. Upon arriving 
near the impressive radio dish, we were disappointed by what we saw. 
The entire parking lot was full of light fixtures that would no doubt 
cause interference. The location is also in a valley in between the 
mountains and we feared that fog might be bad there. By chance, we 
met an individual who was arriving to start his shift, and was 
helpful in suggesting a few sites that would offer much darker skies. 
As the Sun was getting low, we didn't waste any time so we hit the 
road again.

We knew that the nearby Spruce Knob (in Monongahela National Forest) 
was the highest elevated point in West Virginia, and so we headed 
that way. Soon, our GPS indicated we had reached over 4000 feet of 
altitude. As the Sun was just about to hit the horizon, we were 
getting nervous that the dense forest would obstruct our view of the 
sky if we didn't find a spot to setup real soon before it got too 
dark. Finally, after a few minutes of exploring a small dirt road 
going up the mountain, we came up to a flat wide open area with a 
surprising lack of trees. It provided a very decent view of most of 
the sky, including excellent southern horizons. We looked at each 
other and said... "Wow! This is our spot!!!". We began setting up in 
the middle of the field. Unpacking our telescopes and my meteor 
observing coffin was slightly time consuming due to the uneven ground 
and branches from dead trees lying all over the place. We were also 
setting up gear well after sunset, so it was a bit difficult to move 
around. We kept busy most of the evening making sure our telescopes 
(Meade ETX-90 and Celestron C8) were properly polar aligned and ready 
to run piggyback astrophotography. We wrapped our camera lenses with 
heater pads to prevent dew from causing problems. Below us in the 
valleys, we could already see the dreaded blanket of fog! Thank God 
we were at a high elevation! Overhead, the Milky Way in Cygnus was a 
stunning sight to say the least. I could also see the Gegenshein 
fairly easily along the ecliptic.

I signed on at 10:30pm local time. The LEO radiant was still about an 
hour away from rising, but I simply lied back to enjoy the dark 
skies. I plotted for some of the minor showers active at that time. 
Once Michael finished setting up his camera and scope, he also lied 
down to enjoy the gorgeous sky and then went for a short nap. The sky 
slowly improved as the fog gradually dissipated below us and the 
worse of the dew had fallen. The air was still and the area was 
extremely quiet. It was as if we were the only ones under the awesome 
night sky; a very peaceful experience. Every once in a while, I 
logged a sporadic meteor on my chart and recorded my observations. I 
tried to keep my voice down as I knew Michael was fast asleep trying 
to recharge his batteries after spending the entire afternoon driving.

At exactly 11:43pm, the peace was suddenly shattered as I began 
screaming at the first Leonid earthgrazer climbing straight up from 
the east!!! With the Leonid radiant only 1 or 2 degrees above the 
horizon, this most impressive meteor rose from the tree-line and shot 
right past the zenith at a bright magnitude -3. Appearing like a 
rocket, it travelled a length of over 50 degrees. It had vivid 
colors, changing from yellow to blue and flared twice on its path. 
Michael woke-up in a jolt due to my screaming, and immediately 
attended the cameras to begin guided time exposures.

As if somebody had flicked a switch, impressive Leonids earthgrazers 
started appearing on average every 5 minutes. One of them split the 
sky in two with an 80 degrees long path and it flared to magnitude 
-3. Another grazer produced a colorful burst of magnitude -4 in the 
south-west. A particularly memorable sight came at 1:16 local time 
when a pair of 50 degrees long Leonids followed within seconds of 
each-other in the same area in the sky, while a third mag -1 beauty 
appeared only a minute later. All these meteors skimming the upper 
atmosphere were quite awesome!!! After this initial excitement, I 
took a 12 minutes break at 12:45am to rest my voice from yelling so 
much. Besides, I was also very hungry and I needed a piece of sugar 
frosted chocolate cake.

At around 1am local time, the radiant was still low in the east, but 
the Leonids were surprisingly active. I was already seeing an average 
of more than one Leonid every minute. Lots of long paths and bright 
colorful meteors.

By 2am, rates were increasing steadily. I was now averaging two 
Leonids every minute, although there were some periods with bursts of 
a few Leonids within seconds. Beautiful Leonid fireballs of magnitude 
-4 appeared at 1:33am and 1:45am. Both left persistent trains visible 
for up to one minute. Many other meteors were mostly colored yellow.

Just as we hit 3am, the Leonids rates had jumped to an average of 4 
every minute. There were a number of near-simultaneous Leonids. One 
burst of meteors included four Leonids that all shot by within a mere 
two seconds. Bright meteors were still plentiful with several in the 
negative magnitudes. One Leonid was a "point" meteor appearing 
directly on the radiant. It did not have any motion at all except for 
a tiny drifting train. At the bottom of the hour, the meteors kept 
coming faster and faster. The intensifying rates may also have been 
all the more dramatic thanks to the improving sky transparency 
allowing 7th magnitude stars to be seen fairly easily. During one 
occasion, I watched a nice Leonid going down into the south-east 
horizon. At the same time, I saw a brief flash lighting up the sky. 
Then, Michael told me to turn around and face the western sky. Right 
there near the horizon was a thick meteor train from an exploded 
fireball that lingered there for at least *several* minutes!!

At 3:52am, I jumped and screamed (nearly losing my voice) as a burst 
of 10 Leonids all appeared fairly close together in the south within 
just 15 seconds.

At 4am, Leonids average rates were now falling at 10 meteors per 
minute. Keeping track of magnitudes was starting to become 
challenging as I spoke quickly in my tape recorder while more Leonids 
would shoot overhead. My tape recorder was now running continuously 
to help record the action. There appeared to be a more even mix of 
both bright and faint meteors. Almost every bright Leonids that 
streaked overhead left a train behind, usually lasting a few seconds.

At 4:30am, I abandoned all hopes of trying to record individual 
meteor magnitudes. The Leonids were coming fast enough at this point 
that I felt I couldn't keep up accurately enough. Instead, I started 
to say "BEEP!" in my tape recorder every time I saw one. Between all 
our yelling and my talking clock working like crazy, I'm sure we made 
quite a racket! At 4:45am, a fantastic mag -10 fireball exploded with 
a flash near the horizon and left behind a thick train persisting for 
a few minutes. Too bad I didn't see that one all that well since it 
was some distance away from the center of my field of view.

My best rates were seen shortly before morning twilight began to 
interfere. Despite the annoyingly bright glare cast by the cone of 
the zodiacal light in my field of view, the Leonids were roaring! 
Between 5:10am and 5:40am, I was recording an average of 40 meteors 
per minute!!! They were all over the sky. During the most active 30 
minute period alone, I took note of at least four major fireballs 
ranging in brightness from magnitude -7 to -10 ..dot simply 
stunning!!!!!!

Under brightening morning twilight, it became apparent that the peak 
seemed to occur slightly later than predicted. As the sky got 
brighter, scores of Leonids were still shooting furiously no matter 
where I stared in the sky.

At 6:05am, I finally "signed-off" as my limiting magnitude had 
dropped below 5.0. At this point, I put the tape recorder and clock 
aside, and simply lied back to keep watching casually for another 25 
minutes. I was very impressed by the amount of bright Leonids that 
kept coming in such a bright sky. I'm not sure why, but the Leonids 
seen at this moment had truly gorgeous vivid colors! Most were green 
and blue, but the most amazing was the one that appeared pure 
*RED*!!! I don't think I've ever seen one like that before. Perhaps 
the brightening sky was reducing glare on the brighter meteors and 
that might have contributed to enhance the colors.

At 6:30am, I was pooped out and my vocal cords were hurting. I don't 
even remember falling asleep in my coffin all covered in my tarps, 
but the hot morning Sun sure didn't fail to wake me up. Here I was 
still in winter clothing and the temperature was already at least 
15C! As I woke up, a pick-up truck happened to drive by and the 
person told us that the nearby 4900 feet high "Sky Deck" (offering a 
360 degrees view of the mountains) was apparently jam-packed as of 
4am. I'm actually glad we had this nice quiet spot away from the 
crowd, as it was perfect for all the gear we had.

Good old Murphy definitely *did* pay us a visit at the worse possible 
time. At 4:57am, my tape recorder reached the end of the tape but 
failed to do an auto-shut. At one point, I just happened to remember 
that it would be good to check if the tape was still running okay. To 
my unpleasant surprise, the tape was not turning. I was not 
impressed, and I began to wonder how much data I had lost already. 
Turns out I lost only a mere 45 seconds between the time my tape 
stopped rolling and my inspection of it....whew!!!! Talk about a 
close call. Had I forgotten to inspect the tape, I may very well have 
had zero data for the best part of the Leonids. The astrophotography 
also had a few problems. The mount holding one of the cameras for 
piggyback photos had broken apart and the camera fell to the ground. 
The other camera mounted on my scope doing piggyback photos had a 
mis-loaded film for the last 2 hours before dawn - that film is 
completely blank. Fortunately, Michael quickly managed to setup one 
camera on a small tripod, and got some decent unguided photos near 
the peak time. One photograph taken beside the radiant shows as many 
as 18 Leonids!

For me, this was the finest meteor shower I've ever seen. The 
combination of bright earthgrazing meteors, near storm-level rates 
and exceptionally dark skies was an unforgettable experience. Thanks 
to the excellent sky transparency, I recorded a grand total of 3504 
meteors - that's even more compared to the 1999 storm I saw in Spain. 
I certainly don't regret the 22 hours drive it took to observe this 
year's Leonids! Awe-inspiring... to say the least.

Standard meteor report form follows below, with data included for 
both Leonids and minor showers active that night. There were good 
Taurids by the way - that is until I gave up on them when Leonids got 
me really busy...

Pierre Martin
Ottawa, Ontario




DATE: November 17/18 2001
BEGIN: 3:25 UT (22:25 EST)  END: 11:05 UT (06:05 EST)
OBSERVER: Pierre Martin (MARPI)
LOCATION: Long: -79 35' West; Lat: 38 42' North  Elevation: 4180 feet
City & Province: Spruce Knob (Monongahela Nat'L Forest) West Virginia, U.S.A.
RECORDING METHOD: talking clock/tape recorder
-----------------------------------------------------------------------

OBSERVED SHOWERS: 3-letter code;    		 	radiant position
		LEO (Leonids)				10h12 +22
		TAU (North and South Taurids)		04h44 +22
		AMO (Alpha Monocerotids)		07h36 +01
		DER (Delta Eridanids)			03h56 -01
		IAU (possible Iota Aurigids)		05h00 +37
		SPO (sporadics) 			-
-----------------------------------------------------------------------

OBSERVING PERIODS: 0 = none seen;  / = shower not observed

PERIOD(UT) 	FIELD     Teff F	LM     SPO LEO 	TAU AMO DER IAU
03:25-04:27  	04h19 +15 1.00 1.00	6.63	6   0	 2   1   0   0
04:27-05:25	05h09 +15 0.96 1.00	6.63	8   12   0   1   0   0
05:37-06:38	06h12 +14 1.00 1.00	6.79	7   45   5   0   0   0
06:38-07:38	07h18 +16 1.00 1.00	6.95	17  91   6   2   0   0
07:38-08:38	08h16 +09 1.00 1.00	6.95	13  205  /   /   /   /
08:38-09:39	09h32 +11 1.00 1.00	7.02	12  652  /   1   /   /
09:39-10:40	10h16 +13 1.00 1.00	7.08	9   1836 /   /   /   /
10:40-11:05	11h02 +20 0.42 1.00	5.97	2   571  /   /   /   /
-----------------------------------------------------------------------------
TOTALS:			  7.38			74  3412 13  5   0   0 = 3504
-----------------------------------------------------------------------------
The first column (Period UT) refers to observing periods broken down 
as close as possible to one hour of true observing, in Universal 
Time. The second column (Field) is the area in in the sky where I 
centered my field of view. The third column (TEFF) represents 
effective observing time (corrected for breaks or any time I did not 
spent looking at the sky). One hour = 1.00 teff. The fourth column 
(LM) is the average naked eye limitimg magnitude, determined by 
triangle star counts. All following columns indicate the number of 
meteors for each shower observed.

MAGNITUDE DISTRIBUTIONS:

SHOWER -10  -9  -8  -7  -6  -5  -4  -3  -2  -1   0  +1  +2  +3  +4 
+5  +6	AVERAGE

SPO	 0   0   0   0   0   0	 0   0   0   0   3   3   10  5   15 
25  3	+3.19
LEO	 3   0   3   2   3   3	 8   20  21  47  78  87  215 195 199 
106 4  	+2.18
TAU	 0   0   0   0   0   0	 0   0   0   0	 0   2   1   0   4 
5   1	+3.92
AMO	 0   0   0   0   0   0   0   0   0   0   0   0   0   1   2 
2   0	+4.20
--------------------------------------------------------------------------
TOTALS:  3   0   3   2   3   3	 8   20  21  47  81  92  226 201 220 137 8
--------------------------------------------------------------------------
Note: Magnitude scale is to determine the brightness of sky objects. 
Magnitude -8 is comparable to a quarter moon, magnitude -4 with the 
planet Venus, magnitude -1 with the brightest star Sirius, magnitude 
+2 to +3 with most average naked eye stars and magnitude +6 to +7 are 
the faintest stars the naked eye can see under typical dark 
conditions. A meteor of at least magnitude -3 is considered a 
fireball.meteors, and the average for showers.

SKY OBSCURED:
None
------------------------

Dead time: 17 minutes (2.25 min for plots)

Breaks UT: 5:18 (10 sec), 5:25-5:37, 6:32 (45 sec), 8:49 (45 sec), 
9:57 (60 sec)

------------------------

















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