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(meteorobs) Observation December 12/13 2003
Hi all,
Here's my full report for the Friday Dec 12/13 at the Casselman site...
Setting up at the bottom of a quarry pit helped shield the windchill
factor as the temperature dipped down to -15C. What made the night all
that more interesting was the constant *CRACKING* and *CRASHING* sound
of ice falling from the sides of the walls (we we're setup nowhere near
the walls).
As people setup scopes and equipment, I watched the skies casually for
a while and saw a number of meteors. The skies were very crisp and
above-average transparency to allow as high as mag 5.8 limit despite
the bright Moon. Keeping the Moon's glare hidden with an umbrella made
a big difference! The temperature was -15C, so it's a good thing we
weren't exposed to the wind. Then I wrapped myself inside my big
sleeping bag with some chemical hand warmers and got busy recording.
Over the course of 5.5 hours (effective observing time) I recorded a
satisfying grand total of 133 meteors. Of those, there were 99
Geminids, 4 Monocerotids, 5 antihelions, 3 Sigma Hydrids and 22
sporadics. The top Geminid rate was a decent 24/hr. Rates were not
always constant, sometimes 10 or more minutes would go by without a
single meteor. Then, I sometimes had instances of two or three meteors
all appearing just a quick second or two apart. Many were on the faint
side (mag +3 to +4) with just a few exceptions. The brighter meteors
would be usually colored blue and yellow and less frequently blue/green.
The highlights of the night included a beautiful mag -3 vividly BLUE
colored Geminid at 0709UT that went 20 degrees. At 0815UT, a very
impressive mag -3 blue sporadic shot out of the apex producing a 35 deg
long path and leaving behind a 3 second train. Finally, at 9:36UT, the
two Geminids (a mag 0 and a mag +3) almost perfectly simultaneous was
quite a sight.
I signed off at 5am just before some fast moving clouds started to
interfere. On the way back home, I hit a brief snow squall but I could
still see the Moon and all the stars.
Pierre Martin
Ottawa, Ontario
DATE: December 12/13 2003
BEGIN: 0335 UT (2235 EST) END: 1000 UT (0500 EST)
OBSERVER: Pierre Martin (MARPI)
LOCATION: Long: -75.063 West; Lat: 45.269 North Elevation: 50m
City & Province: Casselman, Ontario, CANADA
RECORDING METHOD: talking clock/tape recorder, cord align method
-----------------------------------------------------------------------
OBSERVED SHOWERS:_____________________________________radiant position
GEM (Geminids)_________________________________0728 +33 MON
(Monocerotids)_____________________________0652 +08
HYD (Sigma Hydrids)____________________________0836 +01
ANT (sporadics from the antihelion)____________0628 +23
NPX (sporadics from the north apex)____________1128 +18
SPX (sporadics from the south apex)____________1128 -12
SPO (random sporadics)
-----------------------------------------------------------------------
OBSERVING PERIODS: 0 = none seen; / = shower not observed
PERIOD(UT)__FIELD___Teff__F_____LM____GEM_MON_HYD_ANT_NPX_SPX_SPO
0335-0435__0417+20__1.00__1.00__5.83__18___1___0___1___0___0___2
0435-0538__0508+24__1.01__1.00__5.80__14___0___1___1___0___0___4
0538-0613__0604+20__0.58__1.00__5.80___9___1___1___1___0___0___4
0642-0743__0526+28__1.00__1.00__5.80__24___0___0___0___1___0___2
0743-0903__0518+42__0.99__1.00__5.80__14___1___0___1___3___0___2
0903-1000__0646+59__0.95__1.00__5.67__20___1___1___1___1___0___3
TOTALS:_____________5.53______________99___4___3___5___5___0__17 = 133
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 limiting magnitude, determined by triangle star
counts. All following columns indicate the number of meteors for each
shower observed.
------------------------
MAGNITUDE DISTRIBUTIONS:
SHOWER
____-3__-2__-1___0__+1__+2__+3__+4__+5_____AVE
GEM__1___0___1___3___8__14__38__26___8____+2.93
MON__0___0___0___0___1___2___1___0___0____+2.00
ANT__0___0___0___1___0___0___2___2___0____+2.80
HYD__0___0___0___0___0___0___2___1___0____+3.33
SPO__1___0___0___0___1___5___8___7___0____+2.73
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): None
------------------------
Dead time: 23.99 min. (for breaks)
Breaks (UT): 0506 (2.5min), 0543 (30sec), 0613-0642, 0805 (40sec),
0830-0850, 0926 (20sec)
-------------------------
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