SailNet Community - Reply to Topic

   Search Sailnet:

 forums  store  


Quick Menu
Forums           
Articles          
Galleries        
Boat Reviews  
Classifieds     
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Charts
Clothing
Electrical
Electronics
Engine
Hatches and Portlights
Interior And Galley
Maintenance
Marine Electronics
Navigation
Other Items
Plumbing and Pumps
Rigging
Safety
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here






Go Back   SailNet Community > Skills and Seamanship > Seamanship & Navigation > Celestial Navigation: Nautical Almanac
 Not a Member? 

Seamanship & Navigation Forum devoted to seamanship and navigation topics, including paper and electronic charting tools.


Thread: Celestial Navigation: Nautical Almanac Reply to Thread
Title:
  

By choosing to post the reply below you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Message:
Trackback:
Send Trackbacks to (Separate multiple URLs with spaces) :
Post Icons
You may choose an icon for your message from the following list:
 

Register Now

In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Click here to view the posting rules you are bound to when clicking the
'Submit Reply' button below


Additional Options
Miscellaneous Options

Click here to view the posting rules you are bound to when clicking the
'Submit Reply' button below


Topic Review (Newest First)
05-08-2012 07:43 AM
hellosailor
Re: Celestial Navigation: Nautical Almanac

"N37.76579, W123.10245. No worries"

Actually, one worry. When co-ordinates are given in the ISO standard format DDD.ddddd that usually means there is an engineer doing the numbers, not a navigator.

Is anyone actually using the ISO format for navigation, rather than either of the conventional navigation formats? DDD.MM.mm or DDD.MM.SS ? Even having just the latter two introduces errors when folks mistake one for the other.
05-08-2012 07:34 AM
Flybyknight
Re: Navigation without electronics

Quote:
Originally Posted by SeppSF View Post
Hello All,

I'll check it out on the weekend. I will try to find this position:
N37.76579, W123.10245. No worries...I'll bring a GPS as well.
You're just SW of St. James Island in the North Farallones.
Dick
04-02-2012 09:48 PM
AdamLein
Re: Celestial Navigation: Nautical Almanac

Nice. That's what practice is for.

By the way, if Procyon's computed LHA is 358°58.4' then I think it makes more sense to round up to 359° for the purpose of indexing Pub 249, no? That means you should use the row above.

Also, you need to interpolate between 5° and 6° of declination. If your computed declination has 11.4' attached, and d = 60', then you need to add 11.4' to Hc, which brings you up to Hc = 43°11.4'. This is a lot closer to your Ho of 42°38.2'.
04-02-2012 07:02 PM
AdamLein
Re: Celestial Navigation: Nautical Almanac

Brent, if he's got a computed altitude, he probably isn't doing a noon sight.
04-02-2012 05:58 PM
Brent Swain
Re: Celestial Navigation: Nautical Almanac

For sun sights , almanacs repeat themselves every 4 years. So get 4 years in a row and you have all the backup you need for sun sights. Even one several years out of date is only about three miles out on sun sights.
I can tell people how to take a noon sight in about 5 minutes.
04-02-2012 03:56 PM
AdamLein
Re: Celestial Navigation: Nautical Almanac

Quote:
Originally Posted by milutin View Post
hello there....
Quote:
Hc -0.57' and Ho is 43deg 38'.2
Sounds like something went wrong when you did the computations. Can you give all the details?

One possibility is that you used an assumed position very far from your actual position. Another is that you used Pub 249 incorrectly, which is very understandable as I mess it up all the time. Make sure you use the correct table, including same name vs. contrary name.

So, what's your AP, what star, and what time of observation?
04-21-2010 10:28 PM
AdamLein
Quote:
Originally Posted by sailjunkie View Post
Adam, places where CN makes sense means warmer climes than PNW. That makes 2 of us!
Everything makes more sense in the tropics
04-21-2010 04:12 PM
sailjunkie Adam, places where CN makes sense means warmer climes than PNW. That makes 2 of us!
04-21-2010 01:06 AM
AdamLein
Quote:
Originally Posted by sailjunkie View Post
However, for coastal cruising in the PNW, piloting skills are a must.
Totally agree. I don't expect to ever resort to CN in our local waters. If I really didn't know where I was, landmarks, bottom contours, and other sources of information from coastal piloting are much more useful and timely.

However, I would like to cruise some day in places where CN skills make sense, so I might as well practice now.

Quote:
While I remain fascinated by celestial navigation, it is usually too cloudy here in the rain forest.
I've been surprised at how often I could get good sights. The right combination of filters often punches through clouds that obscure or blur the sun to the naked eye. Overcast, rainy skies are basically hopeless, but if the sky has patches of bright cloud and dark cloud, the bright spots are often transparent under filters and a crisp solar disc can be seen through them.
04-20-2010 04:06 PM
sailjunkie If this is a bit off-topic then I apologize in advance.

If one is going off-shore, then I can definitely see why mastering celestial navigation is a VERY good idea.

However, for coastal cruising in the PNW, piloting skills are a must. CPS and Cdn. Yachting Assn both offer excellent courses.

While I remain fascinated by celestial navigation, it is usually too cloudy here in the rain forest.
This thread has more than 10 replies. Click here to review the whole thread.

 
Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On


All times are GMT -4. The time now is 04:58 AM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012

The SailNet.com store is owned and operated by a company independent of the SailNet.com forum. You are now leaving the SailNet forum. Click OK to continue or Cancel to return to the SailNet forum.