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 » Online Classroom   »   » Public Discussion of Cel Nav   » Vertex, parallel, meridian, passing distance

Author Topic: Vertex, parallel, meridian, passing distance
 Han posted July 22, 2009 02:18 AM                   I do have a question: is it possible with great circle calculations to calculate the vertex, the intersection with a given meridian and a given parallel and the distance to a given co-ordinat. Example 1: A 12° 45' N 124° 20' EB 34° 00 N 120° 40' W The vertex is 41°19,6' N 160° 06,8' WThe intersection with the meridian of 150° E is 29° 46,2' NThe intersection with the parallel of 40° N is 177° 59' W or 143° 10,3° W Example 2: A 12° 45' N 124° 20' EB 21° 32 N 160° 30' W The ship passes the co-ordinat 19° 05' N 166° 30' E. What is the passing-distance? (answer: 163,7 M) I calculated the answers by hand, but is it possible with the Starpilot TI89? With regards, Han Kuiks From: Amsterdam
 David Burch posted July 22, 2009 12:41 PM                   There are not direct starpilot functions for specific points along the great circle track, but you can calculate the track as precisely as you like and then pull off the values you want. Here is 1° steps output from starpilot program for your first example, where you can find the lat at lon 150 and also the vertex, being the highest lat, and so on.(You may have to do Ctrl + to make the font bigger to read this.)code:`Dist(nm)/Course(T)/Len(nm)/Next Lat/Lon6156.6 050.3° 50.75 013°17.2'/125°00.0'6106.04 050.5° 75.71 014°05.1'/126°00.0'6030.62 050.7° 75.19 014°52.4'/127°00.0'5955.71 051.0° 74.64 015°39.0'/128°00.0'5881.35 051.2° 74.08 016°25.1'/129°00.0'5807.55 051.5° 73.5 017°10.5'/130°00.0'5734.33 051.8° 72.91 017°55.3'/131°00.0'5661.69 052.1° 72.3 018°39.3'/132°00.0'5589.66 052.4° 71.69 019°22.7'/133°00.0'5518.25 052.8° 71.06 020°05.4'/134°00.0'5447.46 053.1° 70.42 020°47.4'/135°00.0'5377.31 053.4° 69.78 021°28.6'/136°00.0'5307.8 053.8° 69.13 022°09.1'/137°00.0'5238.93 054.2° 68.47 022°48.8'/138°00.0'5170.72 054.6° 67.82 023°27.8'/139°00.0'5103.16 054.9° 67.16 024°06.0'/140°00.0'5036.26 055.4° 66.5 024°43.5'/141°00.0'4970.01 055.8° 65.84 025°20.2'/142°00.0'4904.42 056.2° 65.19 025°56.2'/143°00.0'4839.47 056.6° 64.54 026°31.3'/144°00.0'4775.18 057.1° 63.89 027°05.7'/145°00.0'4711.54 057.5° 63.24 027°39.3'/146°00.0'4648.54 058.0° 62.61 028°12.2'/147°00.0'4586.17 058.4° 61.98 028°44.3'/148°00.0'4524.43 058.9° 61.35 029°15.6'/149°00.0'4463.31 059.4° 60.74 029°46.2'/150°00.0'4402.8 059.9° 60.13 030°16.0'/151°00.0'4342.9 060.4° 59.53 030°45.1'/152°00.0'4283.6 060.9° 58.94 031°13.4'/153°00.0'4224.88 061.4° 58.36 031°41.0'/154°00.0'4166.74 061.9° 57.8 032°07.8'/155°00.0'4109.16 062.5° 57.24 032°34.0'/156°00.0'4052.14 063.0° 56.69 032°59.4'/157°00.0'3995.66 063.5° 56.16 033°24.0'/158°00.0'3939.71 064.1° 55.64 033°48.0'/159°00.0'3884.28 064.6° 55.13 034°11.3'/160°00.0'3829.36 065.2° 54.63 034°33.9'/161°00.0'3774.93 065.8° 54.15 034°55.8'/162°00.0'3720.99 066.3° 53.68 035°17.0'/163°00.0'3667.52 066.9° 53.22 035°37.5'/164°00.0'3614.5 067.5° 52.77 035°57.4'/165°00.0'3561.93 068.1° 52.34 036°16.6'/166°00.0'3509.79 068.7° 51.92 036°35.2'/167°00.0'3458.08 069.3° 51.51 036°53.1'/168°00.0'3406.76 069.9° 51.12 037°10.4'/169°00.0'3355.84 070.5° 50.73 037°27.0'/170°00.0'3305.3 071.1° 50.37 037°43.0'/171°00.0'3255.12 071.7° 50.01 037°58.4'/172°00.0'3205.3 072.3° 49.67 038°13.2'/173°00.0'3155.82 072.9° 49.34 038°27.4'/174°00.0'3106.67 073.5° 49.03 038°41.0'/175°00.0'3057.83 074.2° 48.72 038°54.0'/176°00.0'3009.29 074.8° 48.43 039°06.4'/177°00.0'2961.04 075.4° 48.16 039°18.2'/178°00.0'2913.07 076.0° 47.89 039°29.5'/179°00.0'2865.36 076.7° 47.64 039°40.2'/-180°00.0'2817.9 077.3° 47.4 039°50.3'/-179°00.0'2770.67 078.0° 47.18 039°59.8'/-178°00.0'2723.67 078.6° 46.96 040°08.8'/-177°00.0'2676.89 079.2° 46.76 040°17.3'/-176°00.0'2630.3 079.9° 46.58 040°25.2'/-175°00.0'2583.9 080.5° 46.4 040°32.5'/-174°00.0'2537.68 081.2° 46.24 040°39.3'/-173°00.0'2491.62 081.8° 46.09 040°45.6'/-172°00.0'2445.7 082.5° 45.95 040°51.3'/-171°00.0'2399.93 083.1° 45.82 040°56.5'/-170°00.0'2354.28 083.8° 45.71 041°01.2'/-169°00.0'2308.75 084.4° 45.61 041°05.3'/-168°00.0'2263.31 085.1° 45.52 041°08.9'/-167°00.0'2217.97 085.8° 45.44 041°12.0'/-166°00.0'2172.7 086.4° 45.37 041°14.6'/-165°00.0'2127.5 087.1° 45.32 041°16.6'/-164°00.0'2082.35 087.7° 45.28 041°18.1'/-163°00.0'2037.24 088.4° 45.25 041°19.1'/-162°00.0'1992.16 089.1° 45.23 041°19.6'/-161°00.0'1947.1 089.7° 45.23 041°19.5'/-160°00.0'1902.04 090.4° 45.24 041°19.0'/-159°00.0'1856.97 091.0° 45.25 041°17.9'/-158°00.0'1811.89 091.7° 45.29 041°16.3'/-157°00.0'1766.78 092.4° 45.33 041°14.2'/-156°00.0'1721.62 093.0° 45.38 041°11.5'/-155°00.0'1676.41 093.7° 45.45 041°08.4'/-154°00.0'1631.13 094.3° 45.53 041°04.7'/-153°00.0'1585.77 095.0° 45.62 041°00.5'/-152°00.0'1540.32 095.7° 45.73 040°55.7'/-151°00.0'1494.77 096.3° 45.84 040°50.4'/-150°00.0'1449.1 097.0° 45.97 040°44.6'/-149°00.0'1403.31 097.6° 46.11 040°38.3'/-148°00.0'1357.37 098.3° 46.26 040°31.4'/-147°00.0'1311.29 098.9° 46.43 040°24.0'/-146°00.0'1265.04 099.6° 46.6 040°16.0'/-145°00.0'1218.61 100.2° 46.79 040°07.5'/-144°00.0'1171.99 100.9° 47 039°58.4'/-143°00.0'1125.17 101.5° 47.21 039°48.8'/-142°00.0'1078.14 102.1° 47.44 039°38.6'/-141°00.0'1030.88 102.8° 47.68 039°27.8'/-140°00.0'983.38 103.4° 47.93 039°16.4'/-139°00.0'935.63 104.1° 48.2 039°04.5'/-138°00.0'887.62 104.7° 48.48 038°52.0'/-137°00.0'839.32 105.3° 48.77 038°38.9'/-136°00.0'790.74 105.9° 49.07 038°25.3'/-135°00.0'741.85 106.6° 49.39 038°11.0'/-134°00.0'692.65 107.2° 49.72 037°56.1'/-133°00.0'643.12 107.8° 50.07 037°40.6'/-132°00.0'593.24 108.4° 50.42 037°24.5'/-131°00.0'543.01 109.0° 50.79 037°07.7'/-130°00.0'492.41 109.6° 51.18 036°50.3'/-129°00.0'441.43 110.2° 51.57 036°32.3'/-128°00.0'390.05 110.8° 51.98 036°13.7'/-127°00.0'338.27 111.4° 52.4 035°54.3'/-126°00.0'286.06 112.0° 52.84 035°34.4'/-125°00.0'233.43 112.6° 53.29 035°13.7'/-124°00.0'180.34 113.2° 53.75 034°52.4'/-123°00.0'126.8 113.7° 54.22 034°30.4'/-122°00.0'72.78 114.3° 54.71 034°07.7'/-121°00.0'18.28 114.9° 18.35 034°00.0'/-120°40.0'` From: Starpath, Seattle, WA

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