(meteorobs) December 10, 2004 Meteor Observations from California

[Robert Lunsford]

I should not have been out tonight as I am still recovering from a cold. I
tried to sleep earlier but I could not get over the guilt of missing the
first clear night in some time. I finally gave up and headed for the hills
shortly after midnight. It was beautifully clear and crisp as I loaded the
truck with my gear. It remained that way until I ran into some fog in the El
Cajon Valley, some fifteen miles east of home. I thought this was a good
sign as it meant stable air and perhaps a few less lights to put up with.
Within a mile or two from my intended observing site, I encountered a strong
headwind that was blowing dust and debris through the air. I could not
believe how suddenly this occurred! At the Alpine Viewpoint the conditions
were brutal with the wind gusting 40-50mph. The only way I could survive
there was to park in the shadow of one of the large semi-trucks parked out
in the middle of the lot. I would probably either get run over or gag on the
smell of diesel. I decided to forego this site and try the old SDAA asphalt
clearing near Descanso. Conditions were just as brutal there so I decided to
try the Pine Valley Viewpoint as a last resort. By this time (40 miles from
home) I was wishing I had just set up in my driveway! Surprisingly, the wind
at the Pine Valley Viewpoint was tolerable. It still gusted 30-40mph on
occasion but I faced my truck into the wind and the cab blocked the worst of
it. I was still concerned that a sudden just would blow my blankets and
charts back to San Diego so I was holding on as best I could. This may be
the reason rates were low during the first hour. It was just difficult to
concentrate when you think the next gust of wind may deposit you down the
mountain! One good aspect was that the wind made the nighttime temperatures
quite mild. In fact it was 12F degrees warmer at 4000ft than it was along
the coast at sea level.

Now for the meteor activity: As stated above, rates were slow for the first
hour. I did see a negative magnitude Geminid while setting up but it did not
occur during the official watch. Only two Geminids were seen during this
first hour. The highlight of this period was a second magnitude Puppid-Velid
that shot upward through southwestern Monoceros, nearly reaching the belt of
Orion. Very impressive long meteor!

Activity really kicked in the second hour as ten Geminids were recorded. All
of my anthelion meteors (Chi Orionids) were seen during this period
including a very short -6, distinctly green fireball that appeared just over
the southeastern horizon and also fragmented. By this time I had also seen
three slow and short Monocerotids, appearing close to the radiant.

Thankfully during the last hour the wind died down a bit. The meteor
activity fell a bit too. Only three Geminids were seen along with another
long Puppid-Velid that shot some twenty degrees through western Virgo.

All in all it was a good session although I expected a bit more from the
Geminids. I should also mention that like the Monocerotids, all three Sigma
Hydrids seen tonight were short and appeared close to the radiant. While
driving home I also noticed a thin crescent moon rising in the southeast. It
formed a nice sight with nearby Venus and Mars.

December  10, 2004

0945-1048 UT   1.00   6.60    0 ANT  0 COM  2 GEM  1 HYD  1 MON
                                               1 PUP   5 SPO  10 TOTAL

1048-1157 UT   1.00   6.69    3 ANT  0 COM  5 GEM  1 HYD  2 MON
                                               0 PUP   10  SPO  21 TOTAL

1157-1303 UT   1.00   6.70    0 ANT  1 COM  3 GEM  1 HYD  0 MON
                                               1 PUP   10 SPO  16 TOTAL

TOTALS:           3.00   6.66    3 ANT  1 COM  10 GEM  3 HYD  3 MON
                                               2 PUP   25 SPO  47 TOTAL

The first column gives the period watched in Universal Time (UT)
which is PST + 8 hours. The second column gives the percent of that
particular hour actually spent observing the sky (1.00 = 100%, 0.99
= 99%). Time is lost for breaks and plotting. No breaks were taken
tonight. The third column gives the average limiting magnitude estimated
during each period. The last several columns list the activity for expected
active radiants during each period. Quite often no activity is observed and
rates equal zero. Tonight I was facing south with my field of view centered
at 50 degrees altitude. ANT = Antihelion radiant (Xi Orionids), COM =
Coma Berenicids, GEM = Geminids, HYD = Sigma Hydrids, MON =
Monocerotids, PUP = Puppid/Velids and SPO = Sporadics (random
activity).

Location: Pine Valley Viewpoint 116 29' 43" W 32 49' 49" N  ELE = 1300 m

Bortle Scale Estimate: Class 3: Rural Sky

Beginning Temperature/Relative Humidity: 57 F (14 C) 49%
Ending              "               "             "        56 F (13 C) 50%

MAGNITUDES OF INDIVIDUAL METEORS PER RADIANT:

ANT: -6 (1) +1 (0) +2 (0) +3 (1) +4 (1) +5 (0)   AVG: +0.33
COM  0 (0) +1 (1) +2 (0) +3 (0) +4 (0) +5 (0)   AVG: +1.00
GEM:  0 (0) +1 (2) +2 (3) +3 (2) +4 (2) +5 (1)   AVG: +2.70
HYD:  0 (0) +1 (0) +2 (1) +3 (1) +4 (1) +5 (0)   AVG: +3.00
MON: 0 (0) +1 (0) +2 (0) +3 (3) +4 (0) +5 (0)   AVG: +3.00
PUP:   0 (0) +1 (0) +2 (2) +3 (0) +4 (0) +5 (0)   AVG: +2.00
SPO:   0 (2) +1 (4) +2 (3) +3 (6) +4 (8) +5 (2)   AVG: +3.06


Bob Lunsford
San Diego, CA USA