[Prev][Next][Index][Thread]
(meteorobs) Wow! Geminids-96! (Mojave Desert, So Cal)
Hello Everyone,
Greetings from a very warm! San Diego. We are currently experinecing
'Santa Ana' conditions here. This occurs when high pressure trough builds
over the Arizona desert and then pushes all that hot air westward to So
Cal. Instead of the typical cool ocean breazes, we experience stong and
warm eastern winds. It was 70 deg F yesterday and winds were gusting in
the local mountains at 70 MPH! Now to the good stuff......
Yes, Robert and I survived. Our third night (at the second site in the
local L.A. mountains) of the campaign saw the mercury drop to 20 deg F. I
know for folks like Trond (of Norway) that may be 't-shirt weather', but
here in So Cal, 20 deg F is plain coooooold. (Its been 10 years since
the day I cross-country skied thru cornfields in Northern Illinois with
temps at -26 deg F and windchills of -75 deg F!) I do know COLD.
Bob's old Toyota runs remarkably well considering the 250,000+ miles it
has logged. We headed out Thurday afternoon (Dec 12) for the 200 mile NE
drive to the central Mojave Desert (~30 miles E of Barstow, CA). And yes, I
want to mention the very nice California Highway Patrol-boy (locally known
as a CHiP) that stopped us. (I say boy; he looked like a rookie). And yes,
the reason we got pulled over... an overabundance of meteor observing
equipment stacked/crammed to the ceiling in the back seat (tripod/camera,
briefcases, chairs, blankets, food, etc etc.) The CHiP-pie seemed fairly
meteor savvy. When I mentioned the reason for all the gear, "There's gonna
be a helluva meteor shower tonite!", his immediate response was "Really.
That's cool. When is the PEAK?". Seems EVERYONE, regardless of backround,
likes to talk about meteors!.
Bob's desert site was superb. Totally unobstructed horizons. 100
miles visibilty all around. Wonderfully clear dark skies. THe 2 nites (Dec
12/13 and Dec 13/14) were the best meteorobs Ive experienced. The temps got
down to mid-40's deg F. Though I didnt see 1200 meteors like our
DMS-colleagues nor did I see 650 as Robert reported, my 2-night total was
586. And, to my amazement it seems my GEMINID-96 data present a statistical
anomoly of sorts. My final tally for Dec 12/13 = 243 (Teff=5.32), final
tally for Dec 13/14 = 243 (Teff=6.29). What's the chances of that occuring.
Much of my veiwing was before midnite (local time) when the radiant was at
an altitude less than 45-50 deg. Activity was very high as everyone has
been reporting. Cloudless all nite, F was 1.00 thruout.
Below I present, informally, count and magnitude dist tables for the 2
nites. I did NOT watch for XORs on the second nite. Formal submission of
my data to IMO/NAMN is shortly forthcoming:
----------------------------------------------------------
Date: Dec 12/13, 1996
Observer: Joseph D. Assmus
Site: Mojave Desert, Yermo, CA
Time (UT) Teff LM GEM XOR SPO TOT
0300-0400 0.95 6.19 11 1 6 18
0400-0500 0.92 6.30 9 4 12 25
0500-0600 0.87 6.12 30 1 17 48
0600-0700 0.87 6.06 37 0 10 47
0700-0800 0.87 6.20 39 0 7 46
1200-1300 0.84 6.10 50 1 8 59
Total 5.32 6.16 176 7 60 243
Mag -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6 Tot Avg
GEM 1 - - - 1 1 - 5 24 51 55 27 11 - 176 2.5
XOR - - - - - - 1 - - 3 3 - - - 7 2.0
SPO - - - 1 1 - - 2 1 11 22 16 6 - 60 2.9
Tot 1 - - 1 2 1 1 7 25 65 80 43 17 - 243
--------------------------------------------------------------------------
Date: Dec 13/14, 1996
Observer: Joseph D. Assmus
Site: Mojave Desert, Yermo, CA
Time (UT) Teff LM GEM SPO TOT
0200-0300 0.97 6.23 10 2 12
0300-0400 0.93 6.29 25 1 26
0400-0500 0.92 6.33 21 6 27
0900-1000 0.82 6.16 55 8 63
1000-1100 0.87 6.20 26 9 35
1100-1200 0.92 6.23 23 5 28
1200-1300 0.85 6.16 38 14 52
Total 6.29 6.23 198 45 243
Mag -5 -4 -3 -2 -1 0 1 2 3 4 5 6 TOT AVG
GEM 1 - 1 1 8 12 27 40 76 28 4 - 198 2.3
SPO - - - - - 2 2 3 12 16 8 2 45 3.6
TOT 1 - 1 1 8 14 29 43 88 44 12 2 243
-------------------------------------------------------------------------
Some quick notes: 0200 UT translates to 6pm Local Time. Not many SPOs
tha early. What amazed me (and Bob) was the high level of GEM activity
so early (obviously somewhat due to the radiant rising early; Castor cleared
the horizon ~6:30 local time. During my second nite, by 0500 UT
(9pm Local Time), I had already counted 65 meteors. Likewise, my first
nite, my first session went from 7pm to midnite local time. WOW. Before
midnite I had counted 184 meteors. That was nice. Second nite had
noticably brighter GEMs.
Some notables:
- Dec 12/13 at 0317 UT a most magnificant -3 blue GEM, length ~40 deg,
duration ~3 sec, big terminal flare/burst, fragmenting into 4 pieces.
- Dec 12/13 at 0507 UT, a -7 GEM about 50 deg from my cntr of field.
saw the explosion as it terminally bursted. Bob estmates it at -7.
- Dec 12/13 at 0517 UT a beautiful -4 SPO that burst into 5-6 pieces.
- On Dec 13/14, I started at 6pm local time. Wanted to see some of
those loooooong earth-grazers. Here they are:
Time (UT) MAG TYPE Length (deg) Color
0611 2 GEM 90 wht
0625 2 GEM 60 org
0633 3 GEM 60 org
0638 -1 GEM 60 yel
0648 2 GEM 30 wht
0654 2 GEM 60 wht
And lastly, probably the most memorable event. On Dec 12/13 Bob and I
saw 7 GEMs in period of LESS THAN 15-20 sec. That really enabled me to
phyically visualize (?) (huh?) the radiant. Is that what I meant? Guess
so. Hope you all 'get the gist' of what Im trying to convey. That is all
for now.
Just want to close by saying thank you to ALL who filed GEMINID-96
reports. What fun it was to sit with cup of coffee in hand and read
(91 emails) about the GEMINID-96 experinces of Sirko, Rainer, Marco,
Casper, and everyone else around the globe from Hawaii to Ecuador to Croatia
to Scotland. And A big "SORRY!!" to our neighbors to the North (Great
White), that is. Well... there's always next year. Until then, its been a
great campaign. Good-bye to all.
With Regards,
Joseph D. Assmus
Sleep and Circadian Studies, UCSD
San Diego, CA