Where's DZ, Really?
Dubbel Zout at Sea
Nik Ormseth
Sat 4 Feb 2023 22:37
| GPS is great — instantly knowing where you are to within a few feet, anywhere on the globe. Between the boat’s nav equipment and our phones, etc., we have at least eight devices with GPS onboard, so it’s easy to think we'd have plenty of redundancy if one of them were to fail. On the other hand, as we were sailing past lightning strikes a few nights ago, it was also easy to imagine everything electronic onboard getting fried in a single instant. Then where would we be? I’ve had a sextant for years, handed down from Hyko, Bella’s dad, who used it back in his surveying days. And I’ve mostly understood the theory, though until today I’d never actually tried to use it while sailing. But I’d lugged it from Seattle to Portugal (10+ lbs in its metal case) so it was long overdue to try. The photo below tells a very distorted story — in particular, everything being perfectly still — the reality is that we were rolling and pitching all over the place. So while, after 30 minutes of taking the sun’s altitude, I was pretty sure I’d caught the maximum in there somewhere, the precise angle and time… I had no confidence in my measurements. And yet: - According to our GPS, today at local noon (sun at its zenith) we were at: 14° 23’ N 54° 48’ W - According to my sextant sightings and subsequent lookups & math, we were at: 14° 38’ N 54° 47’ W Which is a difference of barely 17 nautical miles! Needless to say, I’ll trust the GPS. Also, that seems like a suspiciously accurate location for a complete beginner — which is to say I suspect coincidence more than accuracy. We’ll see how I do tomorrow.  And of course, the lightning strike that wrecked our electronics would also probably fry any reliable source of time, so the sun sighting would only give us our latitude. Oh well, even with that, we’d get to St Lucia eventually. ;-p |