GPS, Plan B: US Navy teaches celestial navigation as fallback for cyberattack

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The shocking thing about this story isn’t that the USN is reintroducing the teaching of celestial nav, it’s that they stopped teaching it in the first place. This is basic seamanship; what the fuck were they thinking?


Same issue with Morse code. It’s absurd they drop this stuff.

“Sure Mr C-I-C! We don’t need that stuff no more! The computeliers will do it all for us, they run on electrickery”


When you think about post-apocalypse navigation, it doesn’t look good. Latitude is pretty easy for nighttime observations, but determining longitude actually requires not just accurate timepieces but almanac tables of celestial data calculated and compiled.

The FAA doesn’t allow pilots to depend on GPS. It’s acceptable as a secondary system, but you need to be able to get where you’re going without it. They have other electronic aids such as DME and VORs, though, over the USA at least. Those are much less likely to be compromised.


At some point in the last 30 years the Pentagon decided that enlistees couldn’t possibly get some useful stimulation from it. Too many chickenhawks in gummit who looked down on those who served? That explains the state of the VA, maybe there were more systemic effects.

I don’t know anything about seamanship, but I do know that there are a lot of things that fall to the wayside in instruction for any field as a consequence of obsolescence. I had an instructor recently tell me that there was a point where virtually all important organic chemistry reductions were done with Jones reagent which has since fallen out of favor. This is still taught, however, so perhaps it’s a bad example. UV-Vis spectroscopy was never taught to me. I was told by an instructor, “It’s in your book if you want to know more, but it’s not really useful enough that I can justify teaching it to you.” After reading up on it, I couldn’t blame her.

Still, when dealing with say, the end of helium, it seems like we should have as many tools as we can get.

There are a lot of skills that would be useful in the event of (computer failure, power outage, Carrington event, zombie apocalypse) that few people bother to learn outside of survivalists, LARPers, or reenactors. Then one of those things happens and suddenly the old ways become important enough to teach again.
p.s. Gellfex, I refer you to Bowditch’s American Practical Navigator.


“You sunk my battleship!!”

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I’m familiar. Here’s a quote from it “Celestial navigation requires accurate predictions of the geographic positions of the celestial bodies observed. These predictions are available from three almanacs published annually by the United States Naval Observatory and H. M. Nautical Almanac Office, Royal Greenwich Observatory”. Who’s going to be providing them after the apocalypse?

I first saw the name Nathaniel Bowditch on the transom of a classic schooner in Penobscot Bay while sailing there at 15. We visited aboard and were told of her namesake. I wonder if she’s still afloat.

Meh. An iPhone in a gimbal with its camera pointed at the sky can do an infinitely better job of celestial navigation than a human with a sextant and a stack of almanacs.

I’m completely in agreement.
The bonus thing about learning how to do it ‘the old way’ is that it reinforces the idea that you’re self-sufficient.

This reminds me of the old story of the artillery officer who was shown a 4-function calculator, and asked “how well does it work after a bullet goes through it”?
My father’s old naval navigation instruments would most likely have been repairable after being hit by a bullet. His parallel ruler could have been used at a pinch for self-defence. An iPhone doesn’t much like even just getting wet.


Fortunately for post-apocalyptic navigation, all that is likely to be needed is moving up and down the coast; nobody is likely to set off across an ocean. And for that, charts are sufficient.
Actually, if you have power, an accurate world map and can measure latitude, longitude is less significant if you are going across most seas. The Pacific is a very different matter since you are likely to miss islands, but to get from Bristol to New York, say, it is (in a simplified way) enough to hit the latitude of NY and keep going West. Longitude is much more important to sailing ships because they have so little idea of their progress in the East-West direction. But with a big enough fuel supply a motor ship captain will know that, say, about ten days of sailing on the right latitude will get him where he wants to be, and he can simply go point to point and not have to follow the winds around the ocean.

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I still have my sight reduction tables, and my wind-up navigator’s watch. It would be trivially easy to produce a new edition of the Nautical Almanac, although it would take some time to distribute them. (Perhaps we can buy some from the UK Hydrographic Office, since our own US Naval Observatory no longer publishes one.)

I used to teach celestial navigation for the USAF Navigator School; it’s been a while, but it isn’t that hard!


I keep promising myself someday I will learn to sail and navigate. And I couldn’t imagine a sailor that wouldn’t want to know celestial navigation–its like a driver that can’t read road signs.

We’re talking about the US Naval Academy, which trains NAVAL OFFICERS; the only enlisted folks who learn navigation are quartermasters, and they don’t actually DO the cel nav.

Not that it’s difficult to learn; it isn’t, but it does require basic arithmetic and care.

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I very much doubt your father’s ship clock which is necessary to determine longitude is less susceptible to bullets than an iPhone. Heck, I very much doubt the sextant is either (those lenses aren’t exactly made of steel).

As far as waterproofing… well, I’m sure the US Navy could build a waterproof case for less than the cost of teaching every sailor even where Polaris is.