(meteorobs) Observation August 13/14 2008

[Pierre Martin]

I took advantage of Thursday morning's clear sky to catch that last  
hour of moonless skies before dawn.  I arrived at the Moose Creek  
site just before 3:30am EDT, but there was one issue.  It was one of  
the foggiest nights I've ever seen.  I was completely surrounded by  
ground fog, to the point that I could barely make out things on the  
ground that were more than a few metres away.  Thankfully, the fog  
was low enough that the sky was quite observable overhead.  As long  
as I kept my field centered at 60 degrees or higher, the fog didn't  
cause an obstruction.  What surprised me was the visibility of the  
zodiacal light in the east despite the murky horizons.  I was glad to  
have my aluminized tarp to cover my sleeping bag... Within a few  
minutes, the tarp was dripping wet!

In a little over an hour until dawn, I recorded 35 meteors (24  
Perseids, 10 sporadics and 1 antihelion).  I kept an eye for other  
active showers, but none were seen.  Even with the Perseids rates on  
the decline, there was a couple of quick bursts that made the session  
interesting... At 3:46am EDT, a pair of fairly bright Perseids (mag  
-1 and mag +1) were seen just a second apart.  Another "burst" came  
at 4:27am EDT when a Perseid and a sporadic appeared nearly  
simultaneously!  The most impressive meteor came at 4:45am EDT after  
I signed-off recording (due to brightening skies).  It was a mag -2  
sporadic that shot high up with a 2 seconds persistent train.

This summer has been wetter than usual and rather unpredictable.  But  
the past moonless window has been a real treat for me, with 7  
individual sessions (though many of them occurring late at night  
after the skies would clear).

Pierre Martin
Ottawa, Ontario


DATE: August 13/14 2008
BEGIN: 0730 UT (0330 EDT) END: 0840 UT (0440 EDT)
OBSERVER: Pierre Martin (MARPI)
LOCATION: Long: -75.063 West; Lat: 45.269 North  Elevation: 400 ft
City & Province: Moose Creek, Ontario, CANADA
RECORDING METHOD: talking clock/tape recorder, cord align
----------------------------------------------------------

OBSERVED SHOWERS:_______________________________radiant position
KCG (Kappa Cygnids)_______________________________18:56 (284) +58
CAP (Alpha Capricornids)__________________________21:12 (318) -06
ANT (Antihelions)_________________________________22:00 (330) -10
SDA (Delta Aquarids)______________________________23:16 (349) -13
PER (Perseids)____________________________________03:00 (045) +57
SPO (sporadics)
----------------------------------------------------------

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

PERIOD(UT)___FIELD____Teff____F______LM____SPO_PER_KCG_CAP_ANT_SDA

0730-0840___0200+23___1.16___1.00___6.08___10___24___0___0___1___0   
=  35

Note: 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 not spent  
looking at the sky). The 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
_____-1___0__+1__+2__+3__+4__+5______AVE

PER___2___2___4___4___6___6___0_____+2.17
SPO___0___0___0___0___4___4___2_____+3.80
ANT___0___0___0___0___1___0___0_____+3.00

Note: 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) (UT): None

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

Dead time: 20 sec (incl break time)

Breaks (UT):  8:07 (20 sec)