(meteorobs) Observation April 22/23 2007

Pierre Martin dob14.5 at sympatico.ca
Fri Apr 27 18:45:10 EDT 2007


Hello all,

This past Monday morning, I woke up and drove to Bootland Farm (west  
of Ottawa) to observe post-maximum Lyrids.  When I arrived there at  
2:00am EDT, I was greeted by Sanjeev who was out observing with his  
85mm refractor.  The Moon was just setting and the skies were  
improving.  The slight haze that I had noticed earlier in the night  
was also dissipating.  It was nice to be out at a dark sky site  
again!  The Spring Peepers were out in full force, and every now and  
then I could hear the sound of Ruffed Grouse doing their "drum  
beat".  The temperature was nice, and dry.  Overhead, the Milky Way  
and summer stars were rising.  What a nice way to start the week!   
Sanjeev treated me to a nice view of several galaxies all visible at  
once from the Virgo cluster.  I'm always impressed at how much a good  
quality small scope can see under dark skies.

I settled for a two hour meteor watch.  I was pleasantly surprised at  
the overall rates... 39 meteors!  The Lyrids were productive with 20  
seen, even though the predicted maximum was already passed by several  
hours.  I had one instance of a pair of Lyrids appearing less than 3  
seconds apart within about 20 degrees of each other.  Although no  
fireballs were seen, meteor brightness was fairly high.  The  
brightest Lyrid was an almost pure-white mag -2 beauty that shot 20  
degrees low in the south-west before I lost sight of it behind my  
car.  The next nicest Lyrid was a mag -1 meteor that travelled 20  
degrees toward the north and left a sharp 2 sec train.  Other bright  
Lyrids were typically colored either white or blue.

Sporadics rates were quite good too.  The best was a mag -1 yellow/ 
orange earthgrazer at 2:46am EDT that shot very swiftly 30 degrees  
path across northern Ophiuchus, and left a 3 sec train.

By 3:00am, the skies were impressive.  The LM peaked at 6.5, and I  
could see lots of structure in the Milky Way right down to  
Sagittarius!  Even the faint bulge of the Milky Way in southern  
Ophiuchus was starting to show some faint dark lane structures.

At 4:35am EDT, I signed-off just as the sky was beginning to brighten  
with dawn.  I wrapped myself deep into my sleeping bag and promptly  
fell asleep.  At 7:45am, my trusty talking alarm clock woke me up...  
and it was time to pack my stuff and head off to work.  Bootland Farm  
is a wonderful site... remote enough for decently dark skies..... but  
still close enough to make short week-night or pre-dawn sessions  
possible!

Clear skies,

Pierre Martin
Ottawa, Ontario


DATE: April 22/23 2007
BEGIN: 0620 UT (0220 EDT) END: 0835 UT (0435 EST)
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, plotting & cord align
----------------------------------------------------------

OBSERVED SHOWERS:_______________________________radiant position
ANT (Antihelions)__________________________14:56 -16
LYR (Lyrids)_______________________________18:04 +34
ETA (Eta Aquarids)_________________________21:36 -07
SPO (sporadics)
----------------------------------------------------------

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

PERIOD(UT)___FIELD____Teff____F______LM____LYR__SPO__ANT__ETA

0620-0721___1706+22___1.00___1.00___6.43___11___10____1____0
0721-0835___1806+22___1.15___1.00___6.37____9____8____0____0

TOTALS:_______________2.15_________________20___18____1____0 = 39

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

LYR____1___1___2___2___5___2___5___2_____+2.25
SPO____0___2___1___1___3___7___1___3_____+2.50
ANT____0___0___1___0___0___0___0___0_____+0.00

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. The above table contains the magnitudes from all observed
meteors, and the average (last column) for showers.
------------------------

SKY OBSCURED (FOV) (UT): None

------------------------

Dead time: 6 min (incl breaks and plots)

Breaks (UT): 7:38-43




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