(meteorobs) Observation July 28/29 2008

Pierre Martin dob14.5 at sympatico.ca
Sun Aug 10 21:17:52 EDT 2008


I returned to Bootland Farm to observe the pre-dawn hours of Tuesday  
July 29.  It was a beautiful night with the sky approaching mag 6.6  
at times.  The moon became noticeable above the trees by 2:40am EDT,  
but it was reduced to such a thin crescent that the interference was  
minimal.  I kept my field centered to the south.  It was also a  
comfortable night, with no pesky mosquitoes.

I setup for meteors starting at midnight and continued to the morning  
twilight at 4:20am EDT, covering about 3.5 hours of effective  
observing time (minus breaks).  I had my two DSLR cameras with wide- 
angle lenses running on auto-exposures.

I recorded a total of 82 meteors.  The busiest hour produced 31  
meteors alone.  The sporadics made up a good part of the activity  
with 33 seen.  The Delta Aquarids produced low rates the first and  
second hour, were much more active in the third hour, before turning  
almost absent in the final half-hour period.  The Alpha Capricornids  
were mildly active throughout the night, producing some beautiful  
slow meteors.  The Perseids provided a low but constant trickle of  
fast moving meteors.  No Pisces Austrinids or Alpha Cygnids were seen.

The most impressive meteor came at 1:50am EDT while I was taking a  
break from recording meteors to grab a snack.  It was a mag -4 Alpha  
Capricornid seen high up in Lyra.  It crawled slowly, ending with a  
bright blue double-flash, and leaving behind a train for 10 seconds.

Pierre Martin
Ottawa, Ontario


DATE: July 28/29 2008
BEGIN: 0355 UT (2355 EDT) END: 0820 UT (0420 EDT)
OBSERVER: Pierre Martin (MARPI)
LOCATION: Long: -76 29' West; Lat: 45 23' North Elevation: 400 ft
City & Province: Bootland Farm, Ontario, CANADA
RECORDING METHOD: talking clock/tape recorder, cord align
----------------------------------------------------------

OBSERVED SHOWERS:_______________________________radiant position
SDA (Delta Aquarids)______________________________22:36 -16
CAP (Alpha Capricornids)__________________________20:20 -11
ANT (Antihelions)_________________________________21:08 -15
PAU (Pisces Austrinids)___________________________22:44 -30
PER (Perseids)____________________________________01:40 +53
ACY (Alpha Cygnids - non IMO shower))_____________20:40 +50
SPO (sporadics)
----------------------------------------------------------

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

PERIOD(UT)___FIELD____Teff____F______LM____SPO_SDA_CAP_ANT_PAU_PER_ACY

0355-0523___1955+06___1.00___1.00___6.55____8___3___6___0___0___3___0
0523-0634___2121+07___1.00___1.00___6.55___10___3___2___3___0___4___0
0634-0738___2221+08___1.00___1.00___6.49___11__10___3___3___0___4___0
0738-0820___2328+08___0.58___1.00___6.34____4___1___1___1___0___2___0

TOTALS:_______________3.58_________________33__17__12___7___0__13___0  = 
  82

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

SPO___0___0___1__10___8___9___5_____+3.21
SDA___1___0___2___3___4___6___1_____+2.82
PER___1___3___0___4___1___2___2_____+2.15
CAP___0___0___2___2___2___4___2_____+3.16
ANT___0___1___1___1___1___3___0_____+2.57

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: 50 min (incl breaks time)

Breaks (UT): 4:30-40, 4:42-45, 4:50-54, 5:01-06, 5:13-19, 5:33-38,  
5:48-52, 6:26-28, 7:11-15, 7:39-46



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