(meteorobs) Wolf Moon Quadrantids

[Bruce McCurdy]

    Emboldened by our recent successes in observing the Orionids, Leonids, 
Geminids, and Ursids, and beckoned by clear skies and moderate temperatures, 
Alister and I headed out to the Blackfoot observing site in the Beaver Hills 
Dark Sky Preserve yesterday evening for a couple of hours observing just 
after the Quadrantid maximum. Alas, the radiant was low and the Full Moon 
was rising high, reflecting brightly off the snow cover, illuminating a thin 
layer of cirrus from above and below. So wishful thinking on our part turned 
into a fairly paltry session, hardly worth the 150+ km round trip to the 
not-so-dark site.

    Limiting magnitude was somewhere around 4.5 throughout, as I could 
faintly discern the arc of mag 4.2 and 4.3 stars between Polaris and Kochab 
while the 5.0 star in the bowl of the Little Dipper was beyond all but the 
most averted imagination. In two hours Teff I observed just seven meteors, 
including five Quads and two sporadics. The distribution was fairly 
remarkable in that I observed four of the seven in a two-minute span. A 
fluke of small number statistics, most likely.

    During the long lulls between meteors I pondered the terrestrial and 
lunar cycles which affect meteor observers. Our previous successful Quad 
session occurred in 2003, which being one leap cycle ago meant the maximum 
occurred at approximately the same time of day (~ 6 p.m. local time). But 
four years is fairly close to 49.5 lunations, meaning that the Moon was new 
then, compared to painfully full now. Four years from now the max will again 
occur in the early evening but the Moon will again be new. It follows that 
for any meteor shower of relatively stable solar longitude, that a given 
site will have a peak that occurs at a favourable time of night every fourth 
year, and the lunar phases will be roughly opposite from one such occurrence 
to the next. This is particularly important for short-lived peaks like the 
Quadrantids; for us in western North America, high-radiant peaks occur 
around 6 a.m. in 2009, 2013, 2017, etc., with the lunar phases "flipping" 
from roughly first quarter to third and back again.

    A more immediate observation involves much higher-than-usual activity 
among local canines. Pack(s) of coyotes were in full-blown howl on more than 
one occasion, while dogs on local acreages responded with nearly continuous 
barking. I wondered if the Full Moon (the aptly named Wolf Moon) was a 
contributing factor; for sure my previous sample of such "observations" was 
heavily biased towards the dark-of-the-moon which normally draws me to the 
site.

    Bruce
    *****

Date: 2007 January 4 2h-4h UT (MST 2007 January 3 19:00-21:00) Teff 2.00 
hours
Observer: Bruce McCurdy
Site: Beaver Hills Dark Sky Preserve (Blackfoot Staging Area), 50 km east of
Edmonton, Alberta
(53°32'12" N, 112° 46m 48s W, elevation 711 metres)
Primary method: Visual; microcassette recorder and talking watch;
Secondary method: Audio; monitoring by car FM radio for forward scattering
(FM 92.1)
***

02:00-03:00; 2° C.; clear; limiting magnitude 4.5; facing NNW 60°; Teff 1.0 
hour
Time   type   mag.  comment
-----------------------------
02:34  SPO   +2
02:40  QUA +1   wake, yellowish

Quadrantid 1: (+1)
Sporadic 1: (+2)
Total meteors: two
***

03:00-04:00; 0° C.; clear; limiting magnitude 4.5; facing NNW 60°; Teff 1.0 
hour
Time   type   mag.  comment
-----------------------------
03:29  QUA  +3  brief wake
03:36  QUA  +1  peripheral vision
03:37  SPO   +3
03:37  QUA  +3
03:38  QUA  +2  brief wake

Quadrantid 4: +1, +2, +3 (2)
Sporadic 1: +3
***

Observing summary: Teff = 2.0 hours
Quadrantid 5: +1 (2), +2, +3 (2)
Sporadic 2: +2, +3
Total meteors: seven
*****