| my account | login-logout | resources | support | catalog | home | get webcard |

Online Classroom

Post New Topic  New Poll  Post A Reply
search | help desk | commons
  next oldest topic   next newest topic
» Online Classroom   » Celestial Navigation   » Public Discussion of Cel Nav   » Long Term Almanac for years 1900-2099

Author Topic: Long Term Almanac for years 1900-2099

 - posted December 20, 2018 11:20 PM      Profile for r.orlik           Edit/Delete Post 

I have been working recently on my version of Long Term Almanac. The reason for it was that I want to create something like long term Pub 249 Vol 1 that allows me to correct Hc and Zn for a given year. The original publication is valid only for 5 years. To make it I needed current positions of stars, hence, either I have current NA or I have some sort of LTA. I decided to take a closer look into LTA's topic and eventually compiled my own version. It contains data for Sun, Aries and all 57 navigational stars.

As it is designed to serve for more than a year it needs few more steps to get correct values. The models underneath are hidden and all needed lookup tables are provided. I want to avoid any multiplication / divisions. If such operations are required then one needs to use auxiliary tables and just add corrections.

One should expect accuracy <0.2' for Sun, Aries and stars. In most cases it should be half of it. In other words - it should be within sextant's sight accuracy. I imagine that such LTA can be printed and laminated to make it last for several years.

As an attachment you can see samples for Sun and Aries in December and one star Rigel. This LTA is valid for years 1900-2099 but I also have version for 1800-2199.

Please review it and write what do you think about it.

Best regards,

From: Wroclaw, Poland

 - posted December 23, 2018 10:30 PM      Profile for r.orlik           Edit/Delete Post 
Here is the link to the PDF file with sample Long Term Almanac and all needed tables:

Best wishes,

From: Wroclaw, Poland

All times are Pacific  
Post New Topic  New Poll  Post A Reply Close Topic    Move Topic    Delete Topic next oldest topic   next newest topic
Hop To:

Starpath School of Navigation

Copyright, 2003-2021, Starpath Corporation

Powered by Infopop Corporation