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Author Topic: Text Example on Page 96
 climber posted June 06, 2019 12:37 PM                   On page 96 of the text, in the example for Venus, the LHA for Venus is determined to be 92 degrees. I use H.O. 229 and the tables do not include an LHA of 92 degrees. I took this course several years ago and am reviewing to hone what skills I still have. For the life of me I cannot remember how to find the Hc, d, and Z values for an LHA of 92 using H.O. 229. No matter what approach I take I cannot duplicate the values in the example.The basic question is: For an LHA of between 91 degrees and 269 degrees, how is H.O. 229 used?I'm sure the answer is obvious but I certainly cannot figure it out.Thank you. From: apalachicola
 Capt Steve Miller posted June 06, 2019 02:07 PM                   HO Pub 229 does have LHA between 90* and 269*. You will find those LHAs note at the bottom of the page.Looking at 229 Volume 3 page 361 at the bottom of the page to the far right you will see LHA 92*, 268*, you will also see Latitude SAME name as Declination. Then looking at the column for 45*S Latitude and the row for Declination 24* S, at the intersection you will find - Hc 15* 22.2', d +40.8, Z 71.2*. You would continue as normal for the rest of the reduction using 229. From: Starpath
 climber posted June 06, 2019 02:27 PM                   I knew there was a SIMPLE answer to the question. This is a primary example of the dangers of tunnel vision and the saying “Insanity is doing the same thing over and over again while expecting a different result”. You get locked into one way of looking at things and don’t see the obvious. Flexibility and adaptability are the keys to survival, and navigation.Anyway, thanks. I can’t believe I missed it, but I did. From: apalachicola
 climber posted June 06, 2019 03:03 PM                   OK, now that I’ve got that, let me ask another question. What do you do when you have an LHA of 92 degrees and a declination of 24 degrees N while your latitude is south (or vice-versa) - a “Contrary” situation? I don’t see any way to address this situation as the 92 degree page is all “Same” up to the C-S line.I am thinking that the C-S line is key here but I’m not sure. From: apalachicola
 Capt Steve Miller posted June 06, 2019 06:52 PM                   Upon looking at both 229 and 249 it appears that there is NO solution to that scenario, The body is most likely below the horizon therefore an invalid situation. From: Starpath

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