1. Sight Reductions & Plotting by the NASR Method Homework Solutions
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2. Objectives
Calculate the altitude, intercept and azimuth of sights taken on the sun, moon, planets or stars using the NASR method.
Plot a single celestial LOP from a sight taken on any of the celestial bodies.
Plot a celestial fix using two, three, or more celestial sights.

3. Question 1 b. Plot and label the two-body fix from these sights.
Refer to your Chapter 4 Homework, exercises 1a. and 1b.
a. Use the back of your SR96 forms and reduce the sights of the two bodies by the NASR method.
Answer 1c
Law of Cosines method
Fix: L29°06,0’N, Lo034°17,0’W
NASR method
Fix: L29°06,5’N, Lo034°18,1’W
The plots are virtually identical with only one nm or less difference in latitude or longitude.
c. Compare the fix positions obtained by the two different methods of sight reduction — i.e., Law of Cosines in Chapter 4, and NASR in this chapter. Are the fix coordinates the same? If not, why?
b. Plot and label the two-body fix from these sights.

4. Question 2
During the morning of 5 December while cruising near the Bahamas at L21°45,0’N, Lo072°33,6’W, you obtain sights that you reduce by the NASR method on the following bodies:
A.2.b.
Law of cosines
Fix L21°46,2’N, Lo 072°34,8’W
NASR
Fix L21°47,0’N, Lo 072°35,0’W
The plots by NASR and Law of Cosines methods are virtually identical with less than 1nm difference in either latitude or longitude.
Body Zone Time Intercept Zn
Procyon nm, T 254°
Capella nm, A 312°
Suhail nm, T 198°
Body Procyon Capella Sushail
GHA: 115°11,4’ 151°50,2’ 095°05,3’
Q.2.b. Refer to Chapter 4 Homework, exercise 2. Compare this fix to your Chapter 4 results. Explain the difference, if any
A.2.a. Fix: L21°47,0’N, Lo072°35,0’W
a. Plot and label the three body fix.

5. Sight Reductions & Plotting by NASR
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