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Quiz Answers for "Where in the world"

You & four friends (Tom, Bob, Don & Rick) are on a cruise ship.  Each of you brought along your marine sextants, 2018 Nautical Almanacs, Texas Instruments Voyage 200 calculators and plotting materials to practice your celestial navigation skills.  On August 17^th 2018 just before sun set you spot a small island to the North West of your position.  At 19:20:00 GMT using your sextant to measure the altitude of the Moon’s lower limb, you find the sextant altitude to be 75°  18.5’.  At the same time Tom measures the altitude for Antares and gets a sextant altitude of 71° 22.4’,  Bob obtains a sextant altitude for Rigel Kentarus of  35° 22.7’, Don obtains a sextant altitude for Altar of  31° 37.9’ & Rick  obtains a sextant altitude for Arcturus of  51° 25.2’. Previously you had determined the upper observation deck of the cruise ship to be 88 feet above the water line.  Your sextant’s index correction, IC= -1.6’, Tom’s IC= -1.8’,  Bob’s IC= -0.3’, Don’s IC= -0.4’ & Rick’s IC= -2.1’.  The air temperature is 31°C & the pressure is 1005mb.

Nautical Almanac data for August 17^th 2018 for GMT = 19:00:00

Moon GHA =23° 32.8’ v=12.2 Dec 12° 24.1’ S  d=9.2 HP=56.3’  Moon’s declination is increasing with time

Aries GHA=251° 06.2’

Altar                      SHA=062° 04.5’  Dec=08° 55.3’ N

Antares                SHA=112° 21.9’  Dec=26° 28.2’ S

Arcturus               SHA=145° 52.7’  Dec=19° 05.5’ N

Rigel Kentarus   SHA=139° 47.1’  Dec=60° 54.7’ S

For the Moon                what is Total GHA _28°_23.3’_ __ , Dec _12°_27.2’ S__, Ho___75°  37.4’____

For the Altar                  what is Total GHA__318° 11.5’___ , Dec _8° 55.3’ N  _ , Ho___31° 26.9’____

For the Antares             what is Total GHA__    8°  28.9’___ , Dec _26°  28.2’ S_,  Ho___71°  11.2’____

For the Arcturus            what is Total GHA__ 41° 59.7’_  _ , Dec _ 19° 5.5’ N__,  Ho___51° 13.3’____                                      

For the Rigel Kentarus  what is Total GHA__35° 54.1’___ , Dec __60° 54.7’ S_,  Ho___35° 12.0____

Which bodies provide the best 2 body fix? __Moon_____,  ___Antares_____

Which bodies provide the best 3 body fix? __Altar______, __Arcturus_____, __Rigel Kentarus __

What was your latitude & longitude @ 19:20:00 GMT for the 2 body fix? _8° 29.7’ S_, _14° 19.6’ W__

What was your latitude & longitude @ 19:20:00 GMT for the 3 body fix? _8° 29.9’ S_, _14° 19.7’ W__

What was your latitude & longitude @ 19:20:00 GMT for a 5 body fix using the method for determining position from intercept and azimuth by calculation? ___8° 29.7’ S_, _14° 19.7’ W __  
                                                                                                    (See Nautical Almanac Page 282 paragraph 11)

What island did you spot to the North West just prior to sun set? ___ Ascension _________

Note: The 2 body & 3 body fix was found using the intersections of Circles of Equal Altitude

See attached PDF for details.