Greetings,

Am pretty sure me only had that kind of a problem in calcs, but, anyway, let me share it with you.  Just in case.

Using intercept method. Getting wrong fixes .  Checked anything a few times, every adding/subtraction.  By the way, I knew what the right fix should be. Just doesn't work. Then recollected oldl engineering rule # 0:  If something is going wrong-check constants.  Anyway, found out that when corrected Declination for proper GMT I added the correction "d" without giving any thought why I am doing it. Just added. In my case it was about 10'.  Then, when I checked NA page and looked down the page, I realized that Decl. is decreasing.  And as soon as I subtracted "d", everything worked fine. Again, I'm sure you know it and pay proper attention to the "tendency" in Decl. to put a correct sign to "d".  Then, when you are using , let say, Pub.229, and correct Hc-then the error in "d" for Decl. does affect Hc.  And eventually intercept itself. 

Never I imagined this kind of error would affect the intercept so much.  In my case it did.

Live and learn. ;> ;>

Good day, Shipmates

I went to a pier on Lapu-Lapu island yesterday and spent a few hours taking shots.  As you see below there are two groups of observations - a set in the morning and a set a few hours later - so a fix is possible.  You may use any or all shots averaged to work out the CN position.  My results came to about one nautical mile accuracy with each group averaged.  I used the standard pubs.... I might go back and try the calculator method... practice practice practice....

GPS position = N  10  14.583
                       E  123  57.351

GMT Oct 18, 2018
DIP = 15'
IE = 0
Sun LL

HHMMSS/ DDMM.M

002035   3850.0
002200   3908.2
002347   3934.2
002458   3951.2
002603   4005.0
002705   4021.0
002846   4044.4
002947   4057.6
003125   4120.5
003250   4139.6

035410   6903.0
035617   6853.8
035801   6846.6
035946   6837.1
040124   6828.2
040239   6821.4
040419   6810.6
040532   6804.1
040707   6754.0
040843   6743.4

On my chart one nautical mile is only about 2mm so I'm pretty happy about the accuracy.  I can easily see mountainous islands 30 miles away.

Have fun
Joe

PS... Height of eye might be suspect. 15 feet was a guess, but it might have been two or three feet higher or lower. This might account for the one NM inaccuracy.

Hello Shipmates,

As a kid and up until the age of electronic watches it was not uncommon for me and other common folk to ask a perfect stranger what time they had - even though one had a watch on the wrist or in the pocket.  We verified the accuracy of our watches as a community to help ensure we were on time.

Folks knew their watches so well they might include a disclaimer such as "I have 9:37, but Im probably fast 3 or 4 minutes."

In our town at precisely 6pm an air-raid siren would blast across the community.  One could set a watch to it.

I used to set my wind-up Timex 5 or 10 minutes ahead just to make sure I was on-time for school or work. 

One could call a phone number to get the correct local time (unsupported in the nation in which I currently reside.)

The second hand wasnt used as much to time boiling eggs as to make sure the watch still worked.

Nothing remotely like these things have happened to me in the past 30 years.

These days you are as likely to get a knife in the chest as receive some semblance of accurate time from a stranger.

Even the wearing of wrist watches has become less fashionable as cell phones increase in number, all of which give reasonable time however imperfect.

With cell phone, computer, and gps clocks being off from actual GMT, sometimes by a considerable amount, where can one go, besides WWV, to get accurate GMT?

Ive accessed several of the GMT web sites, including NIST, which say their time is accurate, but even they can differ from each other by several seconds. Knowing my chrono gains a second in about 3 days I usually set it behind a second which gives me a week of reasonably accurate GMT.

What has been your GMT reference, and how accurate has it been?

Smooth sailing
Joe

This is a heads - up , shipmates...

Have you ever seen Mars before?  How about Saturn?  How about Venus?  How about Jupiter?

Well, two of them, Mars and Saturn, are laying close to the moon tonight.... especially Mars - that big beautiful red planet that is the next farthest from the sun after Earth.  Tonight, being the 19th of Sept, you can see Mars just about half a degree or so from the edge of the waxing moon.  Saturn lays just a few degrees to the East of those two. 

Mars and Saturn are about the brightest objects up there and easily identified.  And if you can see Venus in the evening sky as well you will have a wonderful opportunity to get shots of these four bodies at about the same time.  If you can locate Jupiter that makes 5 interesting targets that will give you hours of great planet and moon reduction practice.  Jupiter will be just above and to the left of Venus in the evening sky.  

http://earthsky.org/tonight/moon-saturn-...mber-17-19


good hunting
Joe

The Nories tables sounds intriguing, precision to 1/10th of a minute.  I've never heard of them before and was cruising through the Celestaire catalog when I ran across the book for sale. Just wondering if anyone has experience with them.

Hope it's okay to post a link.
https://www.celestaire.com/product/norie...al-tables/

Hi Shipmates,

Here is a complicated issue - or maybe its a non-issue that Ive made complicated:

When using a calculator to find Hc, does one enter the same whole numbers that are used when looking up Hc/d/Z in 249/229?  Or does one enter into the formula an APLAT, DEC, and LHA with decimal values (degrees:minutes:seconds) included?

I mean, as I try to think logically about this, if you can create your own assumed position (AP) wherever you like, then you can place the AP as close to the DR as you like,  and as close to the body's Zn as possible.  Then the LOP would consistently line up very near the actual HO position reducing error a great deal (as long as the actual position is relatively close to DR).

The same question applies to finding Z...

Tell me what you think!

Joe

Found this funny captioned picture.

Good idea.

Fred

Attached Files

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I was walking down the pier and wharf in Cordova on our little island when I stopped at a local eatery to wet my whistle and water my dogs...  I entered into a conversation with a local or three where we ended up  talking about great dogs.  I told them about the success I had with the local breeds in that they are very bright, easy to train, and loyal.  My example was not only my black dog, Poker, but another tan Philippine dog that I buried with full honors just a year and a half ago (Feebee).  Then one of the men said something that reminded me of something the Pope said; "All good dogs go to heaven" which I repeated. 

I then got a response that made me think... and think some more.

When I lived in Chicago and felt in a religious mood; when I began to think about what heaven must be like I indeed had the impression that heaven must be a warm beach with plenty of tropical fruits and beautiful girls in trim bikinis to lust after.  However, at the time of this latest religious foray this young man said to me that heaven must be a cool place with plenty of hot coffee to drink. Wow... I thought afterwards - Here I am in that tropical heaven I wished for as a youth with plenty of fruit and well - pretty girls that I try not to lust after, but this man's impression of Heaven was Chicago... or Canada... or Alaska... Places where Ive lived and had plenty enough of. 

So what's my point???  I dont know, really... Im still thinking about it... and heaven... What exactly IS it I still wonder?  Obviously it means a lot of different things to lots of different people... But more importantly it means that the church has failed to explain satisfactorily exactly what's in store after that singular yet unavoidable eventuality - an exact knowledge of the here-after; that part of earthly life that everyone dreads...... the end.

I hope, then, when its my time to embark on that great heavenly voyage, that I see Feebee again so I can ask her to forgive me for training her so hard, and also, perhaps, to learn better how to forgive as I would like to be forgiven. 

The dogs and I soon departed for home leaving my new comrades to ponder for themselves the meaning of life and death - and how best to feed their families.  Im wondering now how to keep my animals more comfortable, and how, while Im still around,  to help  fill my Philippine wife  with joy.  Lord knows shes done all she can to reciprocate.

Joe

Hello Shipmates,

Forgive me if this information has been posted previously.

Here is a sextant index correction sheet that is as simple and elegant to read as they come.

Captain Melas sent this short, understandable, and efficient page to me in an effort to teach an old salt new tricks. 

Captain Diego Melas has also created a web page both lovely to look at and generous in its method at teaching navigation both off shore and inshore.  I appreciate his kindness and tireless efforts to beat new information into my stubborn head.

This morning I used the instructions to correct the index error on a borrowed sextant and came away with a better understanding of the process and the machine.  As we used to say in the Navy - "A piece of cake...!"

Give your sextant the best accuracy its capable of by carefully aligning it's mirrors; but more importantly, have fun.
https://sidaerum.com/
joe

Thomas Dolby wrote the song Oceanea which is a rather nice song.

In various portions of the video a sextant is shown.

Here's a link- https://www.youtube.com/watch?v=7STUTxwdC5A

Dolby was popular many years ago.  His "office" or studio is in an old lifeboat named "Nutmeg".

He's a rather interesting man in his portrayal or attire of the 1920's or so.

The Morse code at the end reads, Atomic Sakhalin, which is an atomic powered lighthouse in Russia...and I assume Sakalin island.


Paul