FROM 1-2. Hobart (Tasmania)-Dunedin (NZ)

Jan 16, 2005 - 0014hrs | (Sydney Time) 47’03”S 163’36”E. 758nm 5.8knts

[ed: this log is operating on Sydney time which is 11 hrs ahead of UTC (GMT)]

Another slightly hazy starlit night with little wind, but there is a gale warning for NZ area Puysegur which we are sailing into. Very impressed with NZ satcom weather service – simple forecasts, easy to interpret and perhaps even accurate.

Have been listening on CD to 1000 years in a Day – ABC production b’cast 31/12/99 while we were sheltering in Skeleton Bay. readings from C11 japanese court lady’s Pillow book – one of her lists was ‘things near but distant’ and included ‘the course of a boat’. Interesting. And i thought of all y’all out there reading this and how distant are you really, and, for me, the size of what we are trying to do and the concepts of nearness and distance and what would Magellan or Drake or Cook or Baudin have been able to achieve with the technology that i have here to play with – GPS, weather forecasts by satellite, email by HF, even a boat that goes to windward – and how tenuous is that link anyway – one USB cable to a multiport box with seriously unstable software that I have to fight every time i turn off the laptop…and no backup…so for the time being, as long as our aux alternator keeps churning out wiggly amps, it stays on. You’ll love the track data, Simon.

Thanks for the sunrise explanation, Don – can we post it for everyone else? [ed: appended to the end of this post] Don’t think much of your experimental verification for ratshit compass – what if the kiwis have decided they don’t particularly like the car park they’re in and have started their engine (powered, no doubt by natural gas from all those sheep) and moved themselves and their island further north?

Have reached stalemate with bootferals. They dont seem to mind bleach – probably consult it like we do the doctor – they are however very iffy about sunshine but think they have me cornered cos there ain’t going to be any more of that for weeks…

Now using UTC (GMT for us ancients) and having trouble juggling three time zones in my head.

[ed: The Sunrise Phenomenon from Don Price, CSIRO]:

Dear Professor Sumner Whitworth,

I hope you haven’t been inundated by explanations to your question about the apparent direction of the sun at sunrise in your neck of the woods.

I can offer two possibilities, which, in keeping with 2005 being the International Year of Physics, you can test experimentally.

1. Your compass is ratshit, and if you continue on your present course you will run ashore somewhere up the west coast of New Zealand.

2. It is due to the unfathomable complexities of 3-dimensional solid geometry. Since you are clearly a man of letters (and very elegant ones

lately) rather than numbers, I will give a simple example rather than try to explain what can best be explained with a pencil and paper or a ball. If you were to sail a little further south, to ~67.5 deg. S in mid-summer, then, as you know, the sun would just touch the horizon at ~ midnight, i.e. sunset and sunrise would occur at the same time. At what bearing would the sun appear at this time? I think the answer is due south – the S pole would be directly between you and the sun. With little imagination, you can guess that as you travel north from this latitude, sunrise will gradually move eastwards.

The tests you should conduct are: 1 – maintain your present course and see if you hit NZ, or 2 – take a hard right turn and head for the antarctic circle and see if the sunrise moves round to 180 deg.

Of course it will be a little more complicated than this. There will undoubtedly be refraction effects in the damp atmosphere, so an exact calculation will be difficult, but try one of the simple tests first.

I await the results of your experiments with interest. Keep up the good work – we’re following your progress with interest.

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