NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Lunar Distance in Wikipedia
From: Frank Reed
Date: 2007 Nov 04, 21:49 -0500
From: Frank Reed
Date: 2007 Nov 04, 21:49 -0500
I wrote earlier: "By 1800, there were many practical methods for clearing lunars available which reduced the total time for the calculation (from beginning to end, including calculating local apparent time) to twenty minutes or even less." Michael you asked: "Is there a good reference for this? Something suitable for Wikipedia? " Sure. You could reference E.J. White's article from 1887. He quotes ten minutes as the time to clear a lunar observation using Thomson's tables. Thomson's tables were first published in 1824. From 1767 through the early 19th century, the calculation time was between ten and twenty minutes. Prior to 1767, the navigator had to calculate the Moon's celestial latitude and longitude which took several hours. After 1767, the lunar distances were tabulated in the almanac. That was responsible for the big savings in time. -FER http://www.HistoricalAtlas.com/lunars --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to NavList@fer3.com To , send email to NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---