[Prev][Next][Index][Thread]
(meteorobs) July 28 Observations
-- [ From: Robert Lunsford * EMC.Ver #2.5.3 ] --
I watched for slightly less than 6 hours this morning from the Descanso
observatory with George Zay. Skies were much more cooperative tonight as
it remained clear the entire morning. I counted a total of 110 meteors
which may sound impressive but it should have been more as there were
several long gaps of inactivity throughout the night. SDA activity was
low the first two hours due to low altitude. After 1am local time the
SDA's came to life but rates were below average for this date. The CAP's
were seen throughout the night and produced two beautiful fireballs (a -
4 blue heading southwest and a white -5 in the "Great Square" of Pegasus
. Both Capricornids had several bursts and the -5 left a 2 second train.
The NDA's also came to life after two hours but were faint with an
average magnitude of only +3.80. The 7 PAU's seen are probably a record
number for me during one session. They were present during 4 of the 6
hours and the most notable member was a nice white first magnitude PAU
heading up toward Aquila. The Perseids were weak (at least for this
shower) all night. The top hourly rate was only 3. None were brighter
than +2 which is surprising. The SIA's were present in low numbers
during the first four hours of the session. These meteors were also
faint. Sporadic activiyt also seemed weak especially during my third
hour when only two were seen. Of course there is always the chance that
some sporadic activity were imitating the many showers active this
morning and misclassified.
Since both George and I were using cassette recorders we could hear each
others data entry. From my perspective it appears that we would agree on
both magnitude and shower association three quarters of the time which
means our data should be fairly similar. We shall see when he posts his
data.
I will also be out tonight and hopefully the activity will be a bit more
steady with more SDA, PER, and SPO action. The other showers reached or
exceeded expectations and hopefully will produce a repeat performance.
July 28, 1998
0610-0710 UT 1.00 6.40 1 ACG 2 CAP 2 SDA 2 SIA 7 SPO 14
TOTAL
0710-0810 UT 1.00 6.45 1 CAP 2 PAU 3 PER 2 SDA 1 SIA 6
SPO 15 TOTAL
0810-0910 UT 1.00 6.47 3 CAP 5 NDA 2 PER 10 SDA 1 SIA 2
SPO 23 TOTAL
0910-1010 UT 1.00 6.49 1 CAP 2 NDA 2 PAU 10 SDA 1 SIA 8
SPO 24 TOTAL
1010-1110 UT 1.00 6.41 1 CAP 2 NDA 2 PAU 1 PER 8 SDA 6
SPO 20 TOTAL
1110-1150 UT 0.67 6.21 2 CAP 1 NDA 1 PAU 2 PER 3 SDA 5
SPO 14 TOTAL
TOTALS 5.67 6.40 1 ACY 10 CAP 10 NDA 7 PAU 8 PER
35 SDA 5 SIA 34 SPO 45 TOTAL
The first column is the period watched in Universal Time (PDT+7 hours).
The second column is the percent of an hour actually spent watching the
sky. Time is lost for breaks, plotting, and data entry. The third column
is the average limiting magnitude during this period with a minimum of 4
estimates per period. The last columns list the activity seen during
each period.
I was facing south southeast at an altitude of 65 degrees. No breaks
were taken during this session. ACY = ALPHA CYGNIDS (DMS), CAP = ALPHA
CAPRICORNIDS, NDA = NORTH DELTA AQUARIDS, PAU = PISCIS AUSTRINIDS, PER =
PERSEIDS, SDA = SOUTH DELTA AQUARIDS, SIA = SOUTH IOTA AQUARIDS and SPO
= SPORADIC (random activity)
Beginning Temperature/Relative Humidity: 63 F (17 C) 46%
Ending Temperature/Relative Humidity: 62 F (17 C) 46%
MAGNITUDES:
ACY +4 (1) AVERAGE : +4.00
CAP -5 (1) -4 (1) 0 (1) +2 (2) +3 (1) +4 (3) +5 (1)
AVERAGE: +1.50
NDA +2 (1) +3 (1) +4 (7) +5 (1) AVERAGE: +3.80
PAU +1 (1) +2 (3) +3 (3) AVERAGE: +2.29
PER +2 (3) +3 (2) +4 (3) AVERAGE: +3.00
SDA 0 (1) +1 (2) +2 (8) +3 (11) +4 (11) +5 (2) AVERAGE +3
.00
SIA +2 (1) +3 (2) +4 (1) +5 (1) AVERAGE: +3.40
SPO +1 (1) +2 (9) +3 (8) +4 (7) +5 (7) +6 (2) AVERAGE +3.
47
Bob Lunsford
San Diego, California USA