NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Perpendicularity check
From: Frank Reed CT
Date: 2004 Sep 22, 23:08 EDT
From: Frank Reed CT
Date: 2004 Sep 22, 23:08 EDT
Alex E wrote:
"I can report some Sun, Moon and stars measurements which I made
from my balcony under the ideal conditions, with an artificial
horizon. These measurements seem to show errors
of about 0.4' (for the Sun) but I do not have an Almanach yet;
I am using the "Complete on board Celestial Navigator" which lists
the Sun position with only 1' precision. I hope that more precise
Almanach data will permit me to explore the ultimate sextant
precision."
I have put together a very accurate Nautical Almanac tool on my web site. It can display almanac data for the standard navigation objects accurate to about 1 arcsecond for the period from 1750 to 2050. The main address for the various tools is
www.HistoricalAtlas.com/lunars
So far, I have found no other software almanacs which are as accurate. Another popular online Nautical Almanac has been assembled by Omar Reis. It's not as accurate as mine, but it is set up to look visually like the pages in the published Nautical Almanac, and some people prefer that formatting. Omar Reis's online Nautical Almanac is located here:
www.tecepe.com.br/scripts/AlmanacPagesISAPI.isa
By the way, I think the "Complete On-board Celestial Navigator" is very clever, and its accuracy is sufficient for the realities of standard late 20th century position line navigation.
Frank R
[ ] Mystic, Connecticut
[X] Chicago, Illinois
"I can report some Sun, Moon and stars measurements which I made
from my balcony under the ideal conditions, with an artificial
horizon. These measurements seem to show errors
of about 0.4' (for the Sun) but I do not have an Almanach yet;
I am using the "Complete on board Celestial Navigator" which lists
the Sun position with only 1' precision. I hope that more precise
Almanach data will permit me to explore the ultimate sextant
precision."
I have put together a very accurate Nautical Almanac tool on my web site. It can display almanac data for the standard navigation objects accurate to about 1 arcsecond for the period from 1750 to 2050. The main address for the various tools is
www.HistoricalAtlas.com/lunars
So far, I have found no other software almanacs which are as accurate. Another popular online Nautical Almanac has been assembled by Omar Reis. It's not as accurate as mine, but it is set up to look visually like the pages in the published Nautical Almanac, and some people prefer that formatting. Omar Reis's online Nautical Almanac is located here:
www.tecepe.com.br/scripts/AlmanacPagesISAPI.isa
By the way, I think the "Complete On-board Celestial Navigator" is very clever, and its accuracy is sufficient for the realities of standard late 20th century position line navigation.
Frank R
[ ] Mystic, Connecticut
[X] Chicago, Illinois
