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Exercise #12 Daylight Sun/Moon Fix
From: Jeremy C
Date: 2008 Jun 6, 01:21 -0700
From: Jeremy C
Date: 2008 Jun 6, 01:21 -0700
Exercise #12 Daylight Sun/Moon fix.
This exercise is for our math friends. It is a series of Moon lines
taken near meridian transit, crossed with an early AM sunline.
Plotting these lines, you will notice an averaged Moon line giving a
decent position with lines within 5 degrees of the horizontal. The
sun line will be nearly vertical and gives a good Longitude line as a
cross.
In this case, my calculations show that Latitude is consistently off,
but the Longitude is within a couple of tenths. I am guessing that my
I wasn�t seeing the actual limb of the moon and therefore was off with
the sextant observations by better than a minute of arc. The moon is
a strange mistress to try and shoot with the sextant.
----------------------------------
UTC date is 28 May 2008. The 21h 00m UTC GPS fix was Latitude 14deg
37.9� North, Longitude 145deg 18.6� East. The Ship is sailing course
090 at 14.3 knots. Height of eye is 106 feet, Temp/Pressure is 84 F
and 1010 MB. Index error is 0.0. The following observations were
made (times in UTC):
Sun (LL): Hs 16deg 43.1� @ 21h 06m 15s
Moon (UL) Hs 72deg 25.6� @ 20h 57m 43s
Moon (UL) Hs 72deg 25.8� @ 20h 59m 14s
Moon (UL) Hs 72deg 25.8� @ 21h 00m 48s
Moon (UL) Hs 72deg 27.2� @ 21h 01m 40s
Moon (UL) Hs 72deg 25.8� @ 21h 02m 20s
Moon (UL) Hs 72deg 26.4� @ 21h 03m 22s
Moon (UL) Hs 72deg 26.0� @ 21h 03m 57s
Moon (UL) Hs 72deg 25.2� @ 21h 05m 08s
Determine a fix at 21h 00 UTC (07h 00m Local)
Jeremy
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