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(meteorobs) Observation August 12/13 2002
On the evening of August 12, I drove out to a site near Franktown
(located south-west of Ottawa). Although this night was predicted to
be clear with good transparency, this wasn't quite the case. The
night was very warm and humid, and had considerable haze and some
passing cirrus clouds. I took a few breaks once in a while to wait
for the clouds to pass by. I was once again running some cameras
with some guided and some unguided shots.
I was able to observe for more than four and a half hours teff.
During this time, I recorded a total of 172 meteors. The Perseids
appeared to have decent early evening activity with a number of
meteors shooting long paths. As the radiant got higher during the
night, the activity rose. However, the rates were considerably
weaker than the previous night. The less-ideal sky conditions and
relentless mosquitoes did not help matters, I suppose.
It was still an enjoyable night of meteors. My fourth hour was the
most active with 48 Perseids. Once again, activity from other minor
showers and the sporadics was below expectations.
There was really one major highlight (seen well before I "signed-on"
for meteors)...
At 17:21 UT, while enjoying the crescent Moon in deep twilight, I
caught sight of one of the most *STUNNING* and *DRAMATIC* meteor I
have ever seen!!!! It wasn't a Perseid meteor.... a sporadic! It
was a very VERY slow fireball that suddenly caught my eye below
Hercules. It was vivid golden-yellow. As it literally "crawled" its
way toward the north, it got brighter and brighter until it reached
magnitude -5. The fireball just kept going... and going... and
going........and going..............and going!!!! It took 10-12
seconds to travel over 60 degrees. It felt like an eternity when you
consider that most meteors last a tiny fraction of a second.
Everybody there had plenty of time to have a good look at it. As the
meteor descended in the north, it finished off with a small flash,
then finally disintegrated into 3 fragments. It was fantastic.
Without any doubt the longest lasting meteor I've ever seen! WOW!!!
That sighting alone made my night!!!
DATE: August 12/13 2002
BEGIN: 0309 UT (2309 EDT) END: 0840 UT (0440 EDT)
OBSERVER: Pierre Martin (MARPI)
LOCATION: Long: -76.0669 West; Lat: 45.0453 North Elevation: 50m
City & Province: Franktown, Ontario, CANADA
RECORDING METHOD: talking clock/tape recorder --> cord alignment method
-----------------------------------------------------------------------
OBSERVED SHOWERS:_______________________________________radiant position
KCG (Kappa Cygnids)_____________________1856 +58
CAP (Alpha Capricornids)________________2116 -06
ANT (antihelion source)_________________2212 -10
NDA (North Delta Aquarids)______________2224 -05
SDA (South Delta Aquarids)______________2316 -13
PAU (Pisces Austrinids)_________________2332 -26
PER (Perseids)__________________________0304 +58
napx (sporadics from the north apex)____0312 +32
sapx (sporadics from the south apex)____0312 +02
SPO (random sporadics)
-----------------------------------------------------------------------
OBSERVING PERIODS: 0 = none seen; / = shower not observed
PERIOD(UT)__FIELD____Teff__LM____SPO_PER_KCG_CAP_ANT_NDA_SDA_PAU_napx_sapx
0309-0409___2216+37__1.00__6.11___2__20__0___0___0___0___0___0____0____0
0409-0452___2216+37__0.70__6.03___4__19__0___0___0___0___0___0____0____0
0530-0643___0049+41__1.00__6.14___4__27__0___0___1___0___0___0____3____0
0643-0747___0153+29__1.00__6.16___4__48__0___0___1___0___1___0____0____1
0747-0840___0250+35__0.88__6.06___3__30__0___0___1___0___0___0____3____0
TOTALS:______________4.58________17__144_0___0___3___0___1___0____6____1 = 172
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
SPO: -1(0) 0(00) +1(00) +2(04) +3(05) +4(10) +5(05) AVE: +3.66
PER: -1(3) 0(10) +1(18) +2(31) +3(27) +4(41) +5(14) AVE: +2.72
ANT: -1(0) 0(00) +1(00) +2(00) +3(01) +4(02) +5(00) AVE: +3.66
SDA: -1(0) 0(00) +1(00) +2(00) +3(01) +4(00) +5(00) AVE: +3.0
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. The above table contains the magnitudes from all observed
meteors, and the average (last column) for showers.
------------------------
SKY OBSCURED:
10% from 0435 to 0440 UT. (clouds)
20% from 0440 to 0452 UT. (clouds)
10% from 0601 to 0615 UT. (clouds)
Corresponding F value:
F value: 1.05 (period 0409-0452 UT)
F value: 1.03 (period 0530-0643 UT)
------------------------
Dead time:
- 18.66 minutes used for breaks.
- 0 minutes used for plots.
Breaks (UT): 0434-0435, 0452-0530, 0540-0541, 0548 (20sec),
0615-0619, 0620-0628, 0730-0734, 0807 (20sec)
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