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(meteorobs) Observation August 12/13 2003
Here's my full report for the Perseids peak night August 12/13...
I was setup at the Reserve Faunique La Verendrye, located about two
hours drive north of Ottawa. The skies were clear, except for the
period between 0436-0544UT when a thin sheet of clouds passed by. The
night was quite comfortable to observe, no wind and not much bugs. The
limiting magnitude averaged 5.24, facing exactly due north. I mounted
two large umbrellas on a tripod to shield the bright Full Moon.
Observing for a little over 5 hours teff (effective time), I recorded a
total of 106 meteors. Perseids hourly rates were 9, 20, 24, 23 and 15.
I was glad that the Perseids provided a decent display otherwise
without them, the meteor activity would have been dull under a brightly
lit sky. I recorded only two Aquarids (I lumped all the southern
radiants together since there was no way to separate them due to the
direction I faced in the sky). Other activity included a single Kappa
Cygnid and 12 sporadic meteors.
I saw as many as nine Perseids in the negative magnitudes. The best of
the 0813UT mag -6 blue fireball that plunged straight down to the
north-east, with a terminal flash and leaving behind a 20 sec twisting
train. Another gorgeous Perseid was the mag -5 fireball seen at
0607UT. It was a long 40 degrees path of vivid blue, ending with a
bright flash and a four second train. There were also three more
Perseids that can be considered "fireball-class" at mag -3.
There were also a lot of fainter meteors too. The average magnitude
for the entire Perseids I saw on this night was +2.00. Most meteors
were well spaced apart. There was only one instance of two Perseids
appearing one second apart.
As mentioned earlier in my quick report, it surprised me to see a
handful of casual impressive Perseid earthgrazers near 1UT, under very
bright twilight skies, and without even trying to see them! One of
them went over 60 degrees. When I signed-on at 0215UT, my impression
was that things already seemed to have tapered off a bit.
Another interesting event was an apparent surge of bright Perseids seen
during the cloudy period (0436-0544UT). During that time I was not
recording but only casually watching. Through the cirro-cumulus, only
the brightest stars down to mag +2 were visible. Yet, the Perseids
could still be enjoyed. One of them must have been at least magnitude
-5 as it flashed into a thicker bank of cloud.
I signed off at 0850UT (0450EST) with quickly brightening twilight.
Already, Orion was completely up the horizon!
All in all, it was worth the trek out of town to see the Perseids, even
though a lot was most certainly missed due the moony conditions. I
can't wait for the 2004 Perseids under much more favorable dark skies.
Standard report below...
Clear skies,
Pierre Martin
Ottawa, Ontario
DATE: August 12/13 2003
BEGIN: 0215 UT (2215 EST) END: 0850 UT (0450 EST)
OBSERVER: Pierre Martin (MARPI)
LOCATION: Long: -76 29' West; Lat: 46 59' North Elevation: 400m
City & Province: Reserve Faunique La Verendrye, Quebec, CANADA
RECORDING METHOD: talking clock/tape recorder, cord align method
-----------------------------------------------------------------------
OBSERVED SHOWERS:_____________________________________radiant position
PER (Perseids)_________________________________0252 +58
AQU (combined radiants of Aquarids complex)____2208 -10
KCG (Kappa Cygnids)____________________________1856 +58
NPX (sporadics from the north apex)____________0308 +32
SPX (sporadics from the south apex)____________0308 +02
SPO (random sporadics)
-----------------------------------------------------------------------
OBSERVING PERIODS: 0 = none seen; / = shower not observed
PERIOD(UT)__FIELD___Teff____F____LM____PER_AQU_KCG_NPX_SPX_SPO
0215-0316__Polaris__1.01__1.00__5.30____9___1___0___0___0___0
0316-0436__"________1.33__1.00__5.20___20___0___0___0___0___5
0544-0644__"________1.00__1.08__5.25___24___0___0___0___0___1
0644-0744__"________1.00__1.00__5.23___23___1___0___0___0___0
0744-0850__"________0.95__1.00__5.05___15___0___1___1___0___5
TOTALS:_____________5.29_______________91___2___1___1___0__11 = 106
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). The fourth column (F) is a value for obstructions in the field of
view such as clouds (1.00 = 100% clear skies). The next 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
_____-6__-5__-4__-3__-2__-1___0__+1__+2__+3__+4_____AVE
PER___1___1___0___3___3___1___6__10__16__33__17____+2.00
AQU___0___0___0___0___0___0___0___0___0___2___0____+3.00
KCG___0___0___0___0___0___0___0___0___0___1___0____+3.00
SPO___0___0___0___0___0___0___0___0___3___4___5____+3.16
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 (FOV): 10% from 0544 to 0554, 5% from 0554 to 0605
------------------------
Dead time: 10 minutes
Breaks (UT): 0217 (40sec), 0436-0544, 0624 (20sec), 0753-0802
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