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(meteorobs) August 13, 2002 Meteor Observations from California
The clouds that caused so much trouble the previous night moved out
leaving a perfectly clear sky for tonight. I tried to nap before heading
out but couldn't. I decided to head out early and try to view some
Perseid earthgrazers. Virtually all of the 18 Perseids seen before
10:00pm were earthgrazers. Most of them were faint and nearly all of
them hugged either the northwestern or eastern horizon. Perseid rates
slowly climbed throughout the session peaking between 10-11UT (3-4am
PDT). The 39 Perseids per hour confirms my thoughts that the 11/12 would
be slightly better than the 12/13, at least from my vantage point on the
west coast. There will be no doubt next year as Aug. 12/13 will be the
better night. It is always this night the year before a leap year. It
won't matter much as it coincides with the full moon in 2003. From what
I saw I would agree that this was one of the weakest Perseid displays in
memory. I have had better rates in the past with the moon in the sky!
Despite the low numbers, there were still some impressive fireballs.
Colors were quite vivid this year with the most impressive being a pure
copper colored Perseid seen Monday morning. Most of the colors I saw
were orange, followed by yellow and blue. The minor shower numbers were
unimpressive. Sporadic rates seen this morning were about what I
expected. It would have been very quiet before 10pm had not the Perseids
been in action. I must work tonight but I plan a couple of more 3 or 4
hour sessions on Thursday and Friday mornings.
August 13, 2002
0430-0600 UT 1.50 6.68 18 PER 1 SDA 2 SPO 21 TOTAL
0600-0700 UT 1.00 6.53 15 PER 1 KCG 6 SPO 22 TOTAL
0700-0800 UT 1.00 6.47 20 PER 1 SDA 6 SPO 27 TOTAL
0800-0900 UT 1.00 6.39 25 PER 1 CAP 1 KCG 2 NDA 1 SDA 8 SPO 38 TOTAL
0900-1000 UT 1.00 6.39 37 PER 2 SDA 1 NPX 1 SPX 9 SPO 50 TOTAL
1000-1100 UT 1.00 6.40 39 PER 2 NDA 3 NPX 1 SPX 9 SPO 54 TOTAL
1100-1200 UT 1.00 6.37 38 PER 1 SPX 7 SPO 46 TOTAL
TOTALS: 7.50 6.48 1 CAP 2 KCG 4 NDA 192 PER 5 SDA 4 NPX 3 SPX
47 SPO 258 TOTAL
The first column gives the period watched stated in Universal Time (UT)
which is PDT + 7 hours. The second column gives the percent of that
particular hour actually spent observing the sky. A cassette recorder
was used to record data tonight so no time was lost recording. The third
column gives the average limiting magnitude estimated during each
period. The last several columns list the activity seen during each
period. I was facing northeast at an altitude of 60 degrees during the
entire session. No breaks were taken. CAP = Alpha Capricornids, KCG =
Kappa Cygnids, NDA = Northern Delta Aquarids, PER = Perseids, SDA =
Southern Delta Aquarids, NPX = Northern Apex, SPX = Southern Apex, and
SPO = Sporadics (random activity).
Location: Deerhorn Valley 116 45' 21" W 32 41' 21" N ELE = 667 m
Bortle Scale Estimate: Class 4: Rural / suburban transition
Beginning Temperature/Relative Humidity: 62 F (17 C) 48%
Ending " " " 61 F (16 C) 45%
MAGNITUDES:
CAP: 0 (1) +1 (0) +2 (0) +3 (0) +4 (0) +5 (0) +6 (0) AVE: +0.00
KCG: 0 (1) +1 (0) +2 (0) +3 (1) +4 (0) +5 (0) +6 (0) AVE: +1.50
NDA: 0 (1) +1 (0) +2 (0) +3 (0) +4 (3) +5 (0) +6 (0) AVE: +3.00
PER: -5 (1) -4 (1) -3 (2) -2 (3) -1 (9) 0 (24) +1 (24)
+2 (36) +3 (42) +4 (37) +5 (11) +6 (2) AVE: +2.15
SDA: 0 (0) +1 (0) +2 (1) +3 (2) +4 (1) +5 (0) +6 (0) AVE: +3.00
NPX: 0 (1) +1 (0) +2 (1) +3 (1) +4 (1) +5 (0) +6 (1) AVE: +2.25
SPX: 0 (1) +1 (1) +2 (0) +3 (1) +4 (0) +5 (0) +6 (0) AVE: +1.33
SPO: 0 (1) +1 (2) +2 (7) +3 (13) +4 (14) +5 (7) +6 (4) AVE: +3.51
Bob Lunsford
San Diego, CA USA
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