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Re: USCG Student Sample Problems #1, #2 and #3
From: Peter Hakel
Date: 2013 Apr 25, 18:15 -0700
From: Peter Hakel
Date: 2013 Apr 25, 18:15 -0700
Hello Kermit, Greg,
I just realized that this difference was caused by a typo on my end: my UT was off by 18 minutes. I mindlessly hit TAB without zeroing out cell E2 (= Minutes of UT) - because all my other almanac spreadsheets already have 00 preset in there... except this Polaris one!
So, indeed Lat: N 23d 23.6' and all is well, see attached. :-) Thanks for digging into this.
Peter Hakel
From: Antoine Couëtte <antoine.m.couette@club-internet.fr>
About POLARIS... and this concerns Peter Hakel this time (are you here Peter ??)
In
" : http://fer3.com/arc/m2.aspx/Group-Project-USCG-student-sample-problems-Couëtte-apr-2013-g23602 "
and from Auxiliary Position 24°N / 143°40' , observing Polaris at UT 05:00:31 at Sextant Height 23°04'1 (corrected for only Instrument Error), I got a Geocentric Height Ho = 22°52'0 (I concur with Greg's published value) and an intercept of -36.4' (Away) in Azimuth 359°5, hence an Observed Latitude of N 23°23'6 at time of observation UT 05:00:31 (or a shifted latitude of N 23°23'7 at UT 05:00:00).
I just realized that this difference was caused by a typo on my end: my UT was off by 18 minutes. I mindlessly hit TAB without zeroing out cell E2 (= Minutes of UT) - because all my other almanac spreadsheets already have 00 preset in there... except this Polaris one!
So, indeed Lat: N 23d 23.6' and all is well, see attached. :-) Thanks for digging into this.
Peter Hakel
From: Antoine Couëtte <antoine.m.couette@club-internet.fr>
About POLARIS... and this concerns Peter Hakel this time (are you here Peter ??)
In
" : http://fer3.com/arc/m2.aspx/Group-Project-USCG-student-sample-problems-Couëtte-apr-2013-g23602 "
and from Auxiliary Position 24°N / 143°40' , observing Polaris at UT 05:00:31 at Sextant Height 23°04'1 (corrected for only Instrument Error), I got a Geocentric Height Ho = 22°52'0 (I concur with Greg's published value) and an intercept of -36.4' (Away) in Azimuth 359°5, hence an Observed Latitude of N 23°23'6 at time of observation UT 05:00:31 (or a shifted latitude of N 23°23'7 at UT 05:00:00).
RE
": http://fer3.com/arc/m2.aspx/Group-Project-USCG-student-sample-problems-Couëtte-apr-2013-g23607 " to which I did not read a reply to.
": http://fer3.com/arc/m2.aspx/Group-Project-USCG-student-sample-problems-Couëtte-apr-2013-g23607 " to which I did not read a reply to.
Peter, while all our other intercepts fully match to +/-
0.1 ' , I still can not reconcile this Latitude I found of 23°23'6 (or 23°23'7) with your value of 23°25'5 published in
" http://fer3.com/arc/m2.aspx/Group-Project-USCG-student-sample-problems-PeterHakel-apr-2013-g23606 ".
" http://fer3.com/arc/m2.aspx/Group-Project-USCG-student-sample-problems-PeterHakel-apr-2013-g23606 ".
Any cue from your part, Peter ?
File:
File: 123694.polaris_corr.xls
