(meteorobs) Observation August 3/4 2011

Wed Aug 10 01:38:42 EDT 2011

I enjoyed another pleasant observing session at Westmeath Lookout, on  
Thursday morning August 4.  This time the sky was completely clear  
with above-average transparency.  Interestingly enough, my average  
limiting magnitude was just slightly lower than the previous session,  
perhaps due to absence of distant clouds which would otherwise help  
block distant light pollution from Ottawa, Renfrew and Pembroke.   
Overhead though, the sky was beautiful with a richly detailed Milky  
Way and a canopy of faint stars.  It also did not take long before I'd  
see a few trained Perseids of the corner of my eye, while I was busy  
carrying and setting up my lawn chair and other items up the hill.

The night was very still and the temperature dropped fast.  The slight  
easterly breeze would eventually die down late at night, allowing  
heavy dewing.  I could also see fog banks in the lower lying areas in  
the valley, but my site was unaffected all night.

I signed on just after midnight (EDT) and I recorded 110 meteors in  
four hours.  There was enough activity every hour to keep me wide  
awake until dawn.  The Perseids were consistently active every hour,  
showing nearly as strong as the sporadic background.  The Delta  
Aquarids were still quite active, even several days after their  
maximum.  The August Piscid radiant seemed to show a minor but  
definite presence, with occasional very swift meteors.  I was  
wondering also if a couple of the sporadics that I saw might be  
associated with the Beta Perseid radiant?
The best meteor was a mag -1 blue-green Perseid at 12:13am EDT that  
shot 20 degrees through the Milky Way, leaving a 2 sec train.  The  
night had a number of interesting satellites, with the following being  
noted:
- 2:19am EDT:  Mag +4 or so satellite flashing rapidly in Pegasus,  
heading slowly east
- 3:44am EDT:  3 satellites in close formation with one object looking  
brighter (mag +2) while the two others were fainter (mag +4) (possible  
NOSS?) passing overhead, heading north.

Pierre Martin
Ottawa, Ontario

DATE: August 3/4 2011
BEGIN: 04:03 UT (00:03 EDT) END: 08:15 UT (04:15 EDT)
OBSERVER: Pierre Martin (MARPI)
LOCATION: Long: -76.859 West; Lat: 45.793 North
City & Province: Westmeath Lookout, Ontario, CANADA
RECORDING METHOD: talking clock/tape recorder, plotting
----------------------------------------------------------

OBSERVED SHOWERS:_______________________________radiant position

PER (Perseids)__________________________________01:58 +54
CAP (Alpha Capricornids)________________________20:22 -10
ANT (Antihelions)_______________________________21:20 -14
SDA (South Delta Aquarids)______________________22:45 -16
PAU (Pisces Austrinids)_________________________22:56 -29
AUP (August Piscids - IMO video database)_______00:30 +18
SPO (sporadics)
----------------------------------------------------------

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

PERIOD(UT)___FIELD_____Teff___LM____SPO_SDA_CAP_ANT_PAU_PER_AUP

04:03-05:03__301 +07___1.00___6.55___9___4___0___1___1___8___2
05:03-06:06__317 +07___1.00___6.58__10___4___4___1___0___9___0
06:06-07:06__336 +03___1.00___6.55___9___6___0___1___0___7___4
07:06-08:15__353 +03___1.07___6.48___9___5___1___5___0___8___2

TOTALS:________________4.07_________37__19___5___8___1__32___8  = 110

Notes: The first column (Period UT) refers to observing periods, 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) Teff is  
simply the total time during the observing session spent actually  
watching the sky. Breaks and/or dead time are not included in the  
reported Teff. It is reported in decimal format such that a 60 minute  
observing session would be reported as Teff = 1.00. The column (LM) is  
the average naked eye limiting magnitude seen.  All following columns  
indicate the number of meteors for each shower observed.  For more  
info, see: http://www.namnmeteors.org/guidechap2.html
------------------------

MAGNITUDE DISTRIBUTIONS:

SHOWER
_____-1___0__+1__+2__+3__+4__+5______AVE

SPO___0___4___3___1___6__11__12_____+3.43
PER___1___5___8___5___4___5___4_____+2.16
SDA___0___0___2___2___4___8___3_____+3.42
ANT___0___0___2___0___2___3___1_____+3.13
AUP___0___0___1___1___1___4___1_____+3.38
CAP___0___0___0___1___1___2___1_____+3.60
PAU___0___0___0___0___0___1___0_____+4.00

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: 8 min (breaks)

Breaks (UT): 5:53-56, 7:15-19, 7:36-37

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