A Lunarian Dodderer

Where Next?
Bob Williams
Thu 9 Jun 2011 02:47

Noon Position: 21 33.5 S 175 07.0 E
West sou' west, Speed: 5 knots
South east, F3 gentle breeze
Sunny, warm
Day's run: 100 miles

I regret to report that I have not yet graduated myself into the distinguished league of lunarians.  Despite careful calculations by my reckoning my deck watch has an error of 10 minutes and 14 seconds, whereas I know by more modern methods its error at the time of my lunars was only 2 seconds. 10 minutes and 14 seconds of time is the equivalent of 153.5 minutes of longitude. Now Columbus or Magellan would have been absolutely delighted to have known their longitude to this degree of accuracy, after all there weren't even any charts where they sailed mostly, but in this day and age it is not exactly a useful figure. In desperation I ran the numbers through the computer and it came up with an error of 11 seconds which is probably as good as I could ever hope for, so my sextant technique is sound, just my number crunching needs a great deal more attention.

I have taken another set of lunar distances this afternoon and will start crunching them shortly to see if I can do a better job with this lot. Practice makes perfect, after all it took me quite a while to remember what a cotangent is, which did not help. All this is of course of absolutely no practical value whatsoever apart from keeping me amused and sane … though there may well come a point where it may lead me down a completely different path. To think the old timers used to do this with nothing but tables and a scratch pad. Mind you, I believe that even into the early 20th century anything beyond the basics of celestial was beyond the skills of many ocean going masters.

The wind continues light and steady, 100 miles is not the greatest run but the sailing is very peaceful. The waxing moon, the clear star filled nights, the steady breeze, the gentle waves, and Sylph silently sliding over them would calm even the most troubled soul – crash, bang – except for that damned mainsail!

Back to the lunars.

All is well.