(meteorobs) Observation June 1/2 2011

[Pierre Martin]

Here's my detailed report for last Wednesday's session.  I was hoping  
to verify the presence (or lack of) Tau Herculids near the possible  
1952 trail encounter.  So I went to Bootland, and joined three other  
guys there, who were out with scopes.  Unfortunately, it was a rather  
disappointing night with waves of low and fast-moving clouds coming in  
and out.  During the brief clear spells however, the sky was quite  
transparent with mag 6.4 stars at the zenith.  The patchy clouds also  
silhouetted beautifully against the rising Milky Way.  The night was  
very comfortable, dry and windy.  It was also just cool enough to keep  
the bugs away.

I waited for clouds to part, and signed on at 11:20pm EDT.  I was able  
to stay on for 37 minutes before the next wave of clouds arrived.   
During this time, I saw a few sporadics and a single gorgeous Tau  
Herculid!  It was a mag -1 golden-yellow meteor that descended below  
Lyra in the east, ending near the double star Albireo.  It had a thick  
wake!  Checking the plot on this one confirms a perfect alignment with  
the TAH radiant.  Upon checking my other plots, the two other TAH  
candidates are either too long or mis-aligned by a large distance (for  
even a diffuse radiant) so I called them sporadics.

Clouds seemingly came from nowhere and took over most of the sky.  It  
forced me to stop or just keep watching casually for the next hour or  
so.  At 1:13am EDT, it finally cleared enough to sign back on.  This  
period only lasted 25 minutes, and I got just a single antihelion out  
of it.  After that, it clouded over solidly and I called it quits.

Pierre Martin
Ottawa, Ontario



DATE: June 1/2 2011
BEGIN: 03:20 UT (23:20 EDT) END: 05:38 UT (01:38 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

ANT (Antihelion)________________________________17:24 (261) -23
TAH (Tau Herculids)_____________________________15:44 (236) +41
SPO (sporadics)
----------------------------------------------------------

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

PERIOD(UT)___FIELD______Teff___LM____SPO_ANT_TAH

03:20-03:58__16:50+09___0.61___6.40___5___0___1
05:13-05:38__18:35+10___0.42___6.40___0___1___0

TOTALS:_________________1.03__________5___1___1  = 7


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

SPO___1___0___0___2___0___2___0_____+2.20
ANT___0___0___1___0___0___0___0_____+1.00
TAH___1___0___0___0___0___0___0_____-1.00


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):  10% from 5:15-5:38 (F=1.11 during the second  
period)

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

Dead time: 1.33 min (plotting)

Breaks (UT): 3:58-5:13 (cloudy periods)

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