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(meteorobs) Observation May 10/11 2002
At last, I have decoded my tape for my May 10/11 meteor session. I
spent the weekend of May 10 at a very dark sky star party located
south of North Bay (Ontario). Due to overcast skies for most of the
night, this was a rather brief (but very enjoyable) session that
lasted a little more than one dark hour TEFF right before dawn. This
was pretty much the best I could do to try and hunt down any possible
Eta Lyrids and other activity. I was setup inside my portable meteor
"coffin" that kept me shielded from the wind quite nicely...
The sky started off looking terrific with stars as dim as magnitude
6.8 to 6.9 glimpsed to the naked eye using a direct star count
method. I then proceeded with the IMO's triangle star counts
(triangle 13 in Lyra revealed 6.9 mag stars, while triangle 11 in
Bootes revealed 6.7 mag stars). The Milky Way rising in the east was
quite stunning, and it was also quite neat to see comet Ikeya-Zhang
lying almost exactly at the zenith. I was thrilled just to see this
sky with or without meteors. To top that off, a soft greenish aurora
appeared low in the north.
My limiting magnitude decreased gradually over the course of the
session due to the glow of the morning twilight (resulting in an
overall average of LM=6.52).
Meteor activity rates appeared to be quite normal with 11 seen. This
included 9 sporadics, one Sagittarid and a confirmed Eta Lyrid. I
plotted most meteors. The nicest meteor was the lone Sagittarid
which was a mag 0 vivid blue. It went by in Lyra a fairly long way
from its radiant. The single Eta Lyrid was a bit fainter at mag +2
but also had a distinct blue color.
To finish off in the deep morning twilight, got a nice pass of the
International Space Station.
Pierre Martin
Ottawa, Ontario
DATE: May 10/11 2002
BEGIN: 0710 UT (0310 EDT) END: 0830 UT (0430 EDT)
OBSERVER: Pierre Martin (MARPI)
LOCATION: Long: -79.368 West; Lat: 46.081 North Elevation:50m
City & Province: Powassan, Ontario, CANADA
RECORDING METHOD: talking clock/tape recorder
-----------------------------------------------------------------------
OBSERVED SHOWERS:_______________________________________radiant position
SAG (Sagittarids antihelion source)_____1624 -21
ETA (Eta Aquarids)______________________2252 +01
ELY (Eta Lyrids) _______________________1920 +44
npx (north apex source)_________________2124 -01
SPO (random sporadics)
-----------------------------------------------------------------------
OBSERVING PERIODS: 0 = none seen; / = shower not observed
(method P = shower association according to plots; method C = shower
association directly under the sky)
PERIOD(UT)__FIELD____Teff__LM____SPO__ELY__SAG__ETA___napx
0710-0825___2114+38__1.16__6.52__P 9__P 1__P 1__0_____0
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: +1(1) +2(1) +3(2) +4(2) +5(2) +6(1) AVE: +3.66
ELY: +1(0) +2(1) +3(0) +4(0) +5(0) +6(0) AVE: +2.0
SAG: +1(1) +2(0) +3(0) +4(0) +5(0) +6(0) AVE: 0
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
------------------------
Dead time: 5.33 minutes (incl 3.5 min for plots)
Breaks: 0713 UT (1.5min), 0747 UT (0.33 min)
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