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Dear George,
Thank you for finding the misprint in my table,
and for your other illuminating comments.
(I was surprised myself that averaging of such "so-so"
observations miraculously gave zero error).
I am posting the corrected table, including the
rejected "blunder" observation which was not included in
my earlier posting.
Please notice: it was rejected BEFORE any reduction.
I would always reject such an observation.
I am waiting for your opinion whether my procedure was sound or not.

AP: N 40d27.2'  W 86d55.8'
GMT: 4:00 Oct 24, T=58F Pressure 29.75
Observation from my balcony, height 12ft,
Sextant SNO-T, index correction 0.0', inverting scope.
One of the 6 observations (column 4) was immediately rejected
because it did not follow the pattern of increasing
distances. I reduced with Frank Reed's on-line calculator.
First, each measurement, and then their average.
The third line is the error in the distance, the fourth line
is the error in the longitude:

Moon-Altair:

GMT   4:06:49    4:09:58     4:13:10  4:14:58   4:17:12    4:18:57
DIST  51d22.2'   51d23.3'    51d23.8' 51d22.4'  51d24.1'   51d24.3'
ERD       0.0'      +0.5'       +0.3'    -1.5'     -0.2'      -0.4'
ERL      +0.3'     +13.5'       +8.7'   -44.0'     -7.3'     -12.2'

After the rejection of column 4:
AVERAGE GMT: 4:13:13  AVERAGE DIST: 23.54'
ERROR IN DISTANCE: 0.0' ERROR IN LONG: 0.4'


> It was Alex's lucky day.

I understand this is not a compliment:-)
I will try to repeat it today, thank God, the weather is
perfect.

Alex.

   

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