(meteorobs) Observation July 26/27 2009

Pierre Martin dob14.5 at sympatico.ca
Wed Jul 29 15:52:10 EDT 2009


Here's my report for Monday morning's session at Bootland Farm.  When  
I left home just after 11:30pm, I knew that I was taking a chance.   
But it's been quite a while since I've had some observing in and I was  
getting desperate ;)  The weather was very unstable, with a t-storm  
cell forming in the east, and another one north-west of the city.  The  
satellite image showed just a small opening west of the city, between  
the storms.  When I arrived at the site, the sky was partly clear with  
varying amounts of cloud cover.  It was also very soggy, and there was  
thick ground fog all around.  And the fog was occasionally thick  
enough that the treeline could barely be seen.  Fortunately, the  
southern sky (where most of the radiants are located) was reasonably  
clear.  For the rest of the session, I'd manage to have an average of  
no more than 20% cloud cover in my field of view.  Where it was clear,  
the transparency varied between 1 and 2 out of 5 (with a LM=6.25).  On  
top of that, the entire night had bright lightning flashes - bright  
enough to affect night vision.  As I was setting up my chair, I saw a  
nice Alpha Capricornid descend in the north.  I managed to get just  
over an hour's worth of effective observing time.  I was sometimes  
forced to take a number of long breaks whenever the cloud cover  
increased over 20% of my field of view.

There was some weak activity from all active radiants (11 meteors  
total), although I'm sure that the poor sky conditions reduced the  
rates quite a bit.  There was still a few nice meteors, and even a  
rare Pisces Austrinid that reached mag +1 and climbed with a path of  
over 20 degrees!

Just before 3am EDT, I was forced to sign off due to sky clouding over  
completely and an ever increasing pace of lightning flashes.

Pierre Martin
Ottawa, Ontario


DATE: July 26/27 2009
BEGIN: 04:45 UT (00:45 EDT) END: 06:50 UT (02:50 EDT)
OBSERVER: Pierre Martin (MARPI)
LOCATION: Long: -76 29' West; Lat: 45 23' North Elevation: 400 ft
Observing site: Bootland Farm, Ontario, CANADA
RECORDING METHOD: talking clock/tape recorder, plotting
----------------------------------------------------------

OBSERVED SHOWERS:_______________________________radiant position
CAP (Alpha Capricornids)_________________________20:16 -11
ANT (Antihelion)_________________________________21:04 -15
SDA (South Delta Aquarids)_______________________22:28 -17
PAU (Pisces Austrinids)__________________________22:36 -31
PER (Perseids)___________________________________01:32 +53
SPO (sporadics)
----------------------------------------------------------

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

PERIOD(UT)____FIELD_______Teff____LM____SPO_ANT_CAP_SDA_PAU_PER

04:45-06:50___21:53 +27___1.32___6.25____3___1___1___2___1___3

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), where 1.00 is exactly one hour. 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
______0__+1__+2__+3__+4__+5______AVE

SPO___0___0___0___0___2___1_____+4.33
PER___1___0___0___2___0___0_____+2.00
SDA___0___1___0___1___0___0_____+2.00
ANT___0___0___0___0___1___0_____+4.00
CAP___1___0___0___0___0___0_____+0.00
PAU___0___1___0___0___0___0_____+1.00

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  
(IMO definition). The above table contains the magnitudes from all  
observed meteors, and the average (last column) for showers.
------------------------

SKY OBSCURED (FOV) (UT): None

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

Dead time: 46 min (for breaks)

Breaks (UT): 4:59-5:15, 6:00-25, 6:37-42




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