(meteorobs) Observation July 25/26 2011

[Pierre Martin]

I was out at Bootland Farm this past Tuesday morning for meteor  
observations, going for a little over two hours effective time.  Eric  
Lemay joined me for some wide field imaging of the Milky Way.  He  
described an encounter he had with a black bear at this location just  
a few nights back.  The night was comfortable, with few bugs.  An  
apparently strong but distant t-storm was active below the northern  
horizon.  This caused multiple flashes of lightning through the clear  
sky overhead for most of the session.  The night was damp and humid  
following rain-showers from earlier in the day.  The sky was quite  
decent though with average (3/5) transparency.

The first hour period produced a decent total of 19 meteors.  The  
Perseids were the most active shower source with four members.  Minor  
activity was seen from the other radiants as well.  The second hour  
period was a bit quieter with 13 meteors.  The Perseids were again  
active with four seen.  At 1:50am EDT, a banana shaped crescent Moon  
was spotted over the trees and contributed in lowering the sky's LM a  
bit.  By the end of the second hour, cloud cover began taking over the  
sky so I quit.

The most impressive meteor by a long shot was a spectacular mag -4  
blue-white Perseid at 12:35am EDT that shot across 40 degrees of the  
north-west sky, and left a persistent train visible for 5 seconds.

Pierre Martin
Ottawa, Ontario


DATE: July 25/26 2011
BEGIN: 04:20 UT (00:20 EDT) END: 06:30 UT (02:30 EDT)
OBSERVER: Pierre Martin (MARPI)
LOCATION: Long: -76 29' West; Lat: 45 23' North
Observing site: Bootland Farm, Ontario, CANADA
RECORDING METHOD: talking clock/tape recorder, plotting
----------------------------------------------------------

OBSERVED SHOWERS:_______________________________radiant position

SDA (South Delta Aquarids)______________________22:28 -17
CAP (Alpha Capricornids)________________________20:16 -11
ANT (Antihelions)_______________________________21:04 -15
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_SDA_CAP_ANT_PAU_PER

04:20-05:20__313 +09___1.00___6.43___9___1___2___3___0___4
05:20-06:30__328 +10___1.13___6.32___6___1___1___1___0___4

TOTALS:________________2.13_________15___2___3___4___0___8  = 32


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

SPO___0___0___0___0___1___1___2___4___6___1_____+3.06
PER___1___0___0___0___0___1___2___0___3___1_____+2.25
ANT___0___0___0___0___0___2___0___0___1___1_____+2.75
CAP___0___0___0___0___1___0___0___0___2___0_____+4.00
SDA___0___0___0___0___0___0___0___2___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  
(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: 2 min (break)

Breaks (UT): 6:19-21

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