NavList:

This is a very nice situation for a daylight fix.  The moon was bearing
nearly due east, while Venus at Meridianal transit, was due South.  The sun ends
up bearing about 225 degrees.  This gives us a longitude line, a latitude line, and a
checking sunline.  If we have shot the bodies correctly, we should have an excellent
oppurtunity for a nice fix here.

 

I have computed these sights in two different ways.  I will detail the tabular
assumed position method as outlined in HO 229 and will follow with a computer based
calculation using the program "SkyMate Pro."

 

As I was taught, the given 1530 fix was advanced the 15 minutes (about 2.6nm) along the
the track line to give me a 1545 DR which was used for both methods.  Without
plotting, you could certainly do a mid-latitude sailing to accomplish this same
thing, and probably a bit more accurately as well.  I just did it on the plotting sheet.

 

To plot the fix (also on the attached pdf) I advanced the first two lines to 1545,
but didn't bother to advance the third line.  The method I use to advance is to
advance the AP of the body instead of moving the LOP.  Either method works, but I
find it neater on the plotting sheet to just advance the AP's.

 

For some reason, probably plotting error, my longitude is a bit off on my hand plot
but my computer plot seems to agree more with other solutions, and the GPS.

 

Venus upper transit.

 

Hs   44-25.8
IC      -0.8
Dip     -9.9
-------------
Ha   44-15.1
Body    -1.0
corr    +0.1
------------
Ho   44-14.2

 

Z-dis 90-Ho
90   89-60.0
Ho   44-14.2
-------------
Zdis 45-45.8

 

Dec-hr S 11-28.2
tcorr     -0.9
----------------
Dec    S 11-27.3

 

Zdis-Dec=Lat

 

Zdis 45-45.8
Dec  11-27.3
-------------
Lat  34-18.5'N
-----------------------
-----------------------

 

Sunline (lower limb)

 

Hs   16-44.2
IC      -0.8
Dip     -9.9
-------------
Ha   16-33.5
Body   +13.1
-------------
Ho   16-46.6

 

GMT    0644-52
GHA hr 268-32.4
tcorr   11-13.0
---------------
GHA    279-45.4
+along 129-14.6
---------------
LHA     49
aLat    34N

 

Dec hr    S22-28.5
corr(-.3)     -0.2
------------------
Dec       S22-28.3
d-incr        28.3
d            -45.4
------------------
corr         -21.4
Hc-t       17-08.8
------------------
Hc         16-47.3
Ho         16-46.6
------------------
a              0.7 A

 

Z 132.9
Zn 227.1

 

------------------------
------------------------

 

Moonline (upper limb)

 

Hs    35-57.0
Ic       -0.8
Dip      -9.9
---------------
Ha    35-46.3
Body    +56.2
HP(59.0) +6.4
UL corr -30.0
---------------
Ho    36-18.9

 

GMT         0643-46
GHA hr     161-50.3
tcorr      +10-26.6
vcorr(8.4)     +6.1
--------------------
GHA        172-23.0
+aLong     128-37.0
--------------------
LHA        301
aLat        34N

 

Dec hr       N19-13.6
corr (+11.6)     +8.4
---------------------
Dec          N19-22.0
d incr           22.0
d               +28.5
---------------------
corr            +10.5
Hc-t          35-51.5
---------------------
Hc            36-02.0
Ho            36-18.9
---------------------
a                16.9 T

 

Z 90
Zn 90.2