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Table 4 - pabrides - 07-11-2018
Anyone who has read Table 4 instructions will agree that they are most confusing... I think I know why - there is an error in the document.
Here is the problem: Read along if you have table 4 instructions handy.
OT = Jan. 18d 04h - 7h = Jan. 17d 21h. (so far so good)
Main Table, Jan. 17d OT, E 2 33 (- 5) Dec. S 20 51 (- 12) (still good)
Table b for 20h OT - 4 - 11 (PROBLEM)
AH- here is the problem; the 20 should read 21 as per the OT line above. If the OT was in fact 20, the DEC correction -11 would change to -10)?
Jan.17d 20h OT, corrected E 2 29 (SAME PROBLEM)
Here again the 20 should read 21 as per the OT line above.
These small errors made my life a living hell as I tried to figure out from where they got the 20.....
After realizing the error and a few practice problems I compared the GHA and DEC with an Almanac, I noted only a small difference between the two; less than a minute. That's not too bad for a few sheets of paper good for almost two score years of Sun GHA and DEC data.
joe
RE: Table 4 - EdCa - 07-11-2018
CelNav wrote an explanation for using Table 4 which makes it much simpler to understand.
I don't think Table 4, as presented, was written for mortals.
See his explanation here- https://thenauticalalmanac.com/How%20to%20use-%20TABLE%204-%20GHA%20and%20Declination%20of%20the%20Sun%20for%20the%20Years%202001%20to%202036-%20Argument%20%E2%80%9COrbit%20Time%E2%80%9D.pdf
RE: Table 4 - pabrides - 07-11-2018
(07-11-2018, 10:31 AM)EdCa Wrote: CelNav wrote an explanation for using Table 4 which makes it much simpler to understand.
I don't think Table 4, as presented, was written for mortals.
See his explanation here- https://thenauticalalmanac.com
LOL...Mortals... Yeah, right.
Granted the writing might have been improved, but the example makes it clear as a bell after correction. About 18 years now and everyone still prints the typo... Table 4 is not hard at all after a few practices... I found it more difficult trying to understand the HP tables.
Anyway, Edca, Im still waiting for some volunteer observation data for the CN Challenge. If you are from California you could provide some pretty interesting sites. How about it... Just send the data to me via PM or post it yourself in the CN Challenge thread... Providing some fiction or non-fiction makes it just that more fun... thanks
joe
RE: Table 4 - Rdutton - 07-11-2018
CN has devolved into something too technical more based on "why-it-works-this-way" instead of "how".
I've spent too much time studying Table 4. The explanation CelNav wrote makes it a very easy process.
Maybe the USNO will include that in their next work? (I'm holding my breath).
Roland