(meteorobs) Geminid obs, Sharon Massachusetts, 14 Dec 2004

[Richard Kramer]

Finally !

After an interminable string of clouds and mirk, a chance to log a few 
Geminids. The sky was discouraging at 11PM local time with a thick island 
of stationary cumulus comfortably settled overhead. The horizon showed a 
band of clear sky in every direction, but my stubborn local cumulus were 
refusing to budge. Not very hopeful, at 1AM I went out to take a final look 
at the clouds and was pleasantly surprised to see that they were gone. 
Unfortunately, they were replaced by a general haze which took a big bite 
out of the LM.

Fortunately, bright GEMs were plentiful, almost all of them glowing an 
unearthly, emerald green and most of them leaving brief, luminous trains. A 
couple of the brightest metoers left trains which lasted about 1 second 
before they faded into the murky urban light pollution. I'm sure I was only 
seeing the brightest fraction of what was likely a very active shower.

One highlight of the session was the fastest meteor, by far, that I've ever 
seen. It was a dim sporadic which had to be travelling more than 100 km/sec 
!!!  It was moving so fast that a velocity estimate is extremely difficult. 
It appeared and disappeared so fast that it gave more the impression of an 
arrow straight lightning flash than a meteor. It spanned some 40 degrees 
stretching from north to south, almost parallel to, and just west of, the 
meridian at 07:01 UTC. Dimmer than mag 3, it was the faintest meteor of the 
evening, but spectacular for its velocity.

Activity seemed to be "clumpy." There were a number of near simultaneous 
meteors, sometimes diverging from the radiant in different directions, and 
sometimes seeming to be pairs of particles travelling together and making 
nearly parallel traces when they hit our atmosphere. Once such pair could 
have been mistaken for a skipping entry, a bright short trace starting 
close to the radiant, followed by a longer trace, exactly colinear with the 
first, beginning farther from the radiant and running considerably longer. 
These were definitely two separate particles because the second trace began 
slightly before the first trace was finished. They must have certainly been 
two very similar particles which had been making their journey around the 
sun in close formation for all those years.

After breaking camp for the short walk home, I managed to irritate a 
neighborhood screech owl with my imperfect attempts at a call. He raged 
back at me from the middle of a nearby wetland as the emerald GEMs 
continued to streak overhead during my amble home. It was a delightful way 
to conclude the evening.

Richard

---------

Richard Kramer Sharon MA USA
71 deg 10.87 min W   42 deg 6.53 min N  Elev 220 ft

2004
EST 01:33 14 Dec  to 02:33 14 Dec
UTC 06:33 14 Dec  to 07:33 14 Dec

Showers observed GEM

14 Dec
UTC              Teff   LM     GEM    SPO    Total
06:33 - 06:50    .27    4       4      2       6
06:50 - 07:01    .17    4       6      0       6
07:01 - 07:13    .20    4       0      2       2
07:13 - 07:22    .15    4       7      0       7
07:22 - 07:29    .11    4       5      0       5
07:29 - 07:33    .07    4       0      0       0
TOTAL            .97    -      22      4      26

Magnitude Distributions

          -2  -1   0   1   2   3  TOTAL
GEM       1   1   5   5   5   5    22
SPO       0   0   0   0   2   2     4

Notes:
1. Facing south center of field was between Orion and Gemini
2. Time bins are irregular due to problems with my primary clock, times are 
accurate
3. LM shown as 4, but declined to 2, 30 degrees off the zenith because of 
haze and light pollution. Effectively, obscuration was 10% at LM 2, 35% at 
LM 3, and 50% at LM 4.
4. Temp 27F winds south, steady at 10 km/hr.