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Multiple body problem

Ocean Navigator

  
On Aug. 1, 2002 (use www.thenauticalalmanac.com for 2002 almanac data), you are hove-to at a DR position of 32° 08’ N, 73° 07.5’ W. Your height of eye is 9 feet, and your sextant has an index error of 1.5’ on the arc. At morning twilight, you shoot Deneb, Saturn and Capella with the following results. Reduce all three sights and determine the 0920 GMT fix position. (Use HO 249 Vol. 1 for the stars and Vol. 2 for the planet.)

Body #1 Deneb   Body #2 Saturn   Body #3 Capella
GMT
GHA Aries (hr.)
GHA Aries (min.)
GHA Aries
Ass. long. (W)
LHA Aries

Hs
IC
Dip
Ha
Alt. corr.
Ho
Hc
Intercept
Zn

 09:18:11
084° 47.9’
+ 004° 33.5’
89° 21.4’
–   73° 21.4’
16° 00.0’

38° 28.5’
–      1.5’
–      2.9’
38° 24.1’
 –      1.2’
38° 22.9’
– 38° 31.0’
8.1 nm away
305°

 GMT
v
GHA (hr.)
GHA (min.)
v corr.
GHA Saturn
Ass. long. (W)
LHA

d
Dec. (hr.)
d corr.
Dec. Saturn

Hs
IC
Dip
Ha
Alt. corr.
Ho

d (HO 249)

Hc
Table 5 d corr.
Hc
Ho
Intercept
Zn

 09:19:03
 + 2.2
000° 17.8’
004° 45.8’
+        0.7’
005° 03.6’
 – 073° 04.3’
292° 00.0’

0.0

N 22° 04.7’
+      0.0’
N 22° 04.7’

29° 37.0’
–     1.5’
–     2.9’
29° 32.6’
–     1.7’
29° 30.9’

+ 25

29° 33’
+    02’
29° 35’
– 29° 30.9’
4.1 nm away
081°

 GMT
GHA Aries (hr.)
GHA Aries (min.)
GHA Aries
Ass. long. (W)
LHA Aries
   
Hs
IC
Dip
Ha
Alt. corr.
Ho
Hc
Intercept
Zn
 		 09:20:10
084° 47.9’
+ 005° 03.3’
089° 51.2’
– 072° 51.2’
017° 00.0’

40° 56.5’
–     1.5’
40° 52.1’
–     2.9’
–     1.1’
40° 51.0’
– 41° 01.0’
10 nm away
055°

 
Fix position:
32° 02.5’ N,
73° 09.3’ W

 

 

By Ocean Navigator