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(meteorobs) Observation August 7/8 2002
On Wednesday August 7, I travelled with a group of deep sky observers
to the La Verendrye Forest Reserve (located about 2.5 hours drive
north of Ottawa) to spend two nights of observing. The location is
absolutely incredible... an unused 1.8km long runway offering flat
horizons in most directions, especially the north-west and south-east
where the runway is oriented. This location is remote well-away from
all source of light pollution.
Indeed, the sky was incredible at night. Even with a night rated to
be only "average" transparency, and the occasional passage of cirrus
clouds or haze I had not too much problem seeing above magnitude 7.0.
The Milky Way was glowing so brilliantly it was as if a huge cloud
lit up by the Moon. M33 was easily visible naked eye. The zodiacal
light/band was noticed beginning at 3:00UT in Pisces. As the night
went, the cone of the zodical light kept getting brighter in the
east. It was almost a nuisance ;>
Meteor rates were enjoyable under such dark skies. I recorded a
total of 106 meteors in 3.5 hours. Activity from the Perseids
matched the sporadics background. Throughout the night, I was
running an unguided camera with 50mm f1.4 centered around Polaris.
Among the highlights...
- As we were setting up in deep evening twilight, a spectacular
fireball was glimpsed. About magnitude -5 with some fragmentation
near the end of its path. It was vivid orange and average speed.
- At 6:17UT, a wonderful slow moving mag -3 sporadic fireball. It
was yellow and this one also fragmented into two pieces before fading
away.
- At 7:17UT, a sporadic and Perseid meteor appeared simultaneously!
They were going opposite directions in the same area of the sky - as
if they would almost hit each other.
Pierre Martin
Ottawa, Ontario
DATE: August 7/8 2002
BEGIN: 0355 UT (2355 EDT) END: 0745 UT (0345 EDT)
OBSERVER: Pierre Martin (MARPI)
LOCATION: Long: -76.29' West; Lat: 46.59' North Elevation: 1300 feet
City & Province: Reserve Faunique La Verendrye, Quebec, CANADA
RECORDING METHOD: talking clock/tape recorder --> cord alignment method
-----------------------------------------------------------------------
OBSERVED SHOWERS:_______________________________________radiant position
KCG (Kappa Cygnids)_____________________1856 +58
CAP (Alpha Capricornids)________________2116 -06
ANT (antihelion source)_________________2212 -10
NDA (North Delta Aquarids)______________2224 -05
SDA (South Delta Aquarids)______________2316 -13
PAU (Pisces Austrinids)_________________2332 -26
PER (Perseids)__________________________0304 +58
napx (sporadics from the north apex)____0312 +32
sapx (sporadics from the south apex)____0312 +02
SPO (random sporadics)
-----------------------------------------------------------------------
OBSERVING PERIODS: 0 = none seen; / = shower not observed
PERIOD(UT)__FIELD____Teff__LM____SPO_PER_KCG_CAP_ANT_NDA_SDA_PAU_napx_sapx
0355-0506___2250+24__1.00__7.03__13__07__0___0___1___0___3___0____2____0
0506-0615___2325+23__1.00__6.95__10__10__0___2___1___2___0___0____2____1
0615-0715___0057+23__1.00__7.00__12__15__0___0___2___0___0___0____2____1
0715-0745___0158+23__0.50__6.93__07__10__0___0___1___0___0___0____1____1
TOTALS:______________3.50________42__42__0___2___5___2___3___0____7____3 = 106
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 I did not
spent looking at the sky). One hour = 1.00 teff. The fourth column
(LM) is the average naked eye limitimg magnitude, determined by
triangle star counts. All following columns indicate the number of
meteors for each shower observed.
------------------------
MAGNITUDE DISTRIBUTIONS:
SHOWER
SPO: -3(1) -2(0) -1(0) 0(0) +1(0) +2(07) +3(10) +4(18) +5(13) +6(3) AVE: +3.77
PER: -3(0) -2(0) -1(0) 0(1) +1(5) +2(10) +3(10) +4(08) +5(07) +6(1) AVE: +3.04
ANT: -3(0) -2(0) -1(0) 0(0) +1(1) +2(00) +3(01) +4(00) +5(03) +6(0) AVE: +3.80
SDA: -3(0) -2(0) -1(0) 0(0) +1(0) +2(01) +3(01) +4(00) +5(01) +6(0) AVE: +3.33
NDA: -3(0) -2(0) -1(0) 0(1) +1(0) +2(00) +3(01) +4(00) +5(00) +6(0) AVE: +1.50
CAP: -3(0) -2(0) -1(0) 0(0) +1(0) +2(00) +3(01) +4(01) +5(00) +6(0) AVE: +3.50
Note: Magnitude scale is to determine the brightness of sky objects.
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:
None
Corresponding F value for this session is 1.00
------------------------
Dead time:
- 20 minutes used for breaks.
- 0 minutes used for plots.
Breaks (UT): 0420-0431, 0558-0607
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