NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: HMS Bounty
From: William Allen
Date: 2004 May 19, 09:38 -0700
From: William Allen
Date: 2004 May 19, 09:38 -0700
Fred, Could you please give a little more explanation on using the sine curve to approximate declination? Maybe a short example? Thanks, Bill Allen -----Original Message----- From: Navigation Mailing List [mailto:NAVIGATION-L@LISTSERV.WEBKAHUNA.COM] On Behalf Of Fred Hebard Sent: Tuesday, May 18, 2004 3:21 PM To: NAVIGATION-L@LISTSERV.WEBKAHUNA.COM Subject: Re: HMS Bounty On May 18, 2004, at 5:44 PM, George Huxtable wrote: > How could he have > done this without a table of day-by-day Sun declination, that only the > ephemeris or some other nautical table could provide? Although not accurate to the minute, one can estimate the sun's declination by means of a sine curve running from the equinox as zero degrees to the solstice as 90, with an amplitude of 23.5 degrees. The ellipticity of the earth's orbit is accounted for, more or less, by the varying number of days between the various equinoxes and solstices. Of course, how does one estimate a sine? If one remembers the Taylor expansion for it, that would be one way. It's more likely, from subsequent references in George Huxtable's post, that Captain Bligh had a short table of declinations. An adequate one could fit on one page. Making heroes out of the mutineers is undoubtedly stretching the truth on the Bounty mutiny. But, as captain, it was Bligh's fault, just as in any other catastrophe on a ship. Apparently, however, his charms were no match for those of some of the Tahitian maidens! I told some of the boys who work with me the story of the Hawaiian girls swimming out to Cook's ship to "welcome" him and his crew. Some of those boys are not too unlike some of Cook's sailors I would think. One of them was ready to go to Hawaii on the spot! He had missed that Cook got there 230 years ago. Fred Hebard