- Phil W Lee / Wed, 30 Dec 2015 18:40:03 +0100

.... happy new year to everyone ...


So I made my way by dead reckoning over very minor country lanes. I was
interested to note that I was navigating - or at least, confirming my
direction - by looking at the stars. First time in a long time!

So you are not an Englishman. They doubt the existence of
lights in the sky behind the fog.

It's mostly light pollution that kills our view of the stars these
days, and it affects vast areas, including nearly all cities and
conurbations, not just in the UK, but in most developed countries.
Regular atmospheric pollution makes this worse.

True, light pollution is very impressive when coming home to the
city after a mountain tour.

The night sky is a mystery to MOST people these days, as most live in
those very cities and conurbations that are producing the pollution.

I don't find the link right now -- on youtube, there is a very funny
story told by Neil deGrasse Tyson (the NY astronomer) how, as a boy,
his parents wanted to show the planetarium to him. His (if not true
then well-invented) answer was: »but I already know all four stars
there are in the sky« ...


... In Namibia, I found it was possible (with about 5 minutes
of adjustment for my eyes) to walk safely outside at night by
starlight, with no moon visible.

I can even read in total darkness. At least since I got an iPad
;o)

.... which by the way offers (even free) basic astronomy apps.
A lot easier to learn about star constellations than by books.

But you do confirm my thesis that a sailor / navigator
should have more skills than relying on GPS only.

Even the most simple minded should have a basic knowledge of celestial
navigation - even if it is just locating Polaris (the northern pole
star) or an approximate location of Sigma Octantis (the southern pole
star) - even though that star is not normally visible, it's position
can be located with sufficient accuracy for any normal purpose from
it's fixed position relative to the Southern Cross.

That's what I think about this, too.

It's unbelievably easy to accidentally misdirect a compass with the
strangest of objects ...

.... or GPS. Our city busses have an info system (»next stop: xyz«)
based on GPS. When there is fog or snow in the air, the system tends
to talk total crap.

... so having an absolute reference for direction is
essential, and those two references are visible without too much
difficulty in all but the worst conditions unless obscured by clouds.


Electronics is good, but I'd never trust on it alone.
Even if there are redundand systems. Planes crashed because
pilots were unable to judge which one was defect and which
one to trust.


jk



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