Choose Something Like a Star: The Return of Celestial Navigation
October 17, 2015 3:52 PM   Subscribe

"[S]atellites and GPS are vulnerable to cyber attack. The tools of yesteryear—sextants, nautical almanacs, volumes of tables—are not. With that in mind, the [U.S. Naval] academy is reinstating celestial navigation into its curriculum." A navigation expert speaks about the importance of a lower-tech approach. Want more? Celestial navigation in the classroom. Build your own sextant!
posted by MonkeyToes (34 comments total) 60 users marked this as a favorite
 
The FAA still has a celestial navigation endorsement for airplane pilots. Until the 1950s planes were built with observation domes for shooting the stars. Totally obsolete now in aviation and I don't think anyone's going to bring it back. Training material and exam questions still exist for the endorsement, although there's some question whether you can find a qualified examiner.
posted by Nelson at 4:12 PM on October 17, 2015 [1 favorite]


On a practical level what if you need a bit of nav after a global EMP event, or more mundanely a lightning strike and you forgot your $600 brass sextant and reduction tables at home? What then bucko? Well quite seriously this book: Emergency Navigation: Improvised and No-Instrument Methods for the Prudent Mariner provides practical methods for location and navigation to get home or just to land and a safe port.
posted by sammyo at 4:20 PM on October 17, 2015 [27 favorites]


Back in the seventies when I was a student at UC Santa Barbara, a professor in the physics department gave a free course in how to use a sextant. It was very satisfying to go out to the beach with a sextant, compass, watch, and book of tables. In a few minutes you knew where you were. I want to be able to that again. (I love slide rules, too. )
posted by njohnson23 at 4:55 PM on October 17, 2015 [12 favorites]


As a geographer who has benefitted from the digital geospatial revolution, I do think we shouldn't lose sight of where we came from. I also worry that digital mapping technologies are adversely affecting our paper map reading abilities. I don't think we should go full-on Luddite, but stressing traditional mapping and location finding skills early on will likely make us better users of geospatial technology and more savvy map readers.
posted by mollweide at 5:10 PM on October 17, 2015 [12 favorites]


Previously: The Lost Art of Finding Our Way. An excellent book.
posted by Kirth Gerson at 5:17 PM on October 17, 2015 [11 favorites]


This seems pretty sane and reasonable. Like, it's good to have backup systems, so we're going to make sure this one gets maintained. Not like, "omigosh cyberthreats we must burn all the tech and write contracts for $500,000-a-piece tactical field sextant development."
posted by Wolfdog at 5:18 PM on October 17, 2015 [3 favorites]


In the 80's a friend was working for a school teaching Accounting aboard U.S. Navy ships. He joined the sighting party every day while they sighted the ship's position manually. (he did this to learn the skill for his sailing hobby) This was done despite the availability of GPS. The intention being to keep the skill alive as a backup to GPS. He said the position obtained manually was entered into the ship's log.
So it seems this sensible practice was discontinued to be rejuvenated at this time?
posted by shnarg at 5:21 PM on October 17, 2015


I'm not sure exactly, but I sort of have a hunch the Naval Academy stopped teaching celestial navigation in the late 1990s.
posted by Wolfdog at 5:24 PM on October 17, 2015 [1 favorite]


*searches for iPhone sextant app ... *
posted by ZenMasterThis at 5:26 PM on October 17, 2015 [2 favorites]


Backpackers have always shared this sentiment. A trail GPS is a wonderful thing, but if you're in the backwoods without some kind of backup then you're a fool. Batteries will die on you, electronics will crap out at inopportune times, etc. A map and compass, if you know how to use them (you can learn the bare bones in an hour) will always work. Not to mention, a proper paper map—an object which costs about $10 and unfolds to several square feet—will always give you a much better idea of what the land around you looks like than the shitty 2.5" screen and crappy, expensive charts of a trail GPS. I love a GPS for showing me where I've been (and for telling me the bearing and distance to a known set of coordinates) but give me a map and compass any day for figuring out where I am and how to get where I need to go.
posted by Anticipation Of A New Lover's Arrival, The at 5:30 PM on October 17, 2015 [11 favorites]


Oh, and even if you lack a compass, a map will still get you pretty far if you have a few visual landmarks and the ability to find a rough North.

Plus, topo maps are beautiful objects and, here in the U.S., the result of a truly amazing public mapping effort by the USGS, the products of which are public domain and hence available for free (as digital maps) or at an extremely reasonable cost from backcountry organizations like The Sierra Club and the Appalachian Mountain Club which repackage USGS data into lovely waterproof paper maps and sell them to help fund their conservation and outreach work (and to promote backcountry safety). So, that's cool.
posted by Anticipation Of A New Lover's Arrival, The at 5:38 PM on October 17, 2015 [17 favorites]


Great post! Another map-lover and enthusiastic sailor here.

I bought a 'learner' sextant about 2 years ago, and a book on celestial navigation... regretfully I haven't yet tackled the subject in earnest, but still plan to.

A great resource: Teacup Navigation, which has links to his useful (and freely downloadable) book, plans for a DIY octant, and some free software for sight tables etc.

We have a couple of small GPS units, but I'm sick of watching other boaters glued to their chart plotters (GPS+chart) like 9 year-olds to Saturday AM cartoons, so we mainly navigate with charts and landmarks. I hope to master celestial nav one day.
posted by Artful Codger at 6:15 PM on October 17, 2015 [5 favorites]


Oh man did I love my sextant. It was brass (non corrosive by salt) and second hand so I had to check the calibration. Some junior navigators and schools used plastic ones which were fine but used to warp if left in the sun. I crossed the Atlantic with it and the Indian ocean.
There is a amazing thrill in getting yourself across a vast stretch of the water using a clock and a sextant and hoping that that the clouds don't block the midday sun or screw up the star shots.
I got very into star sights and calculations.
I joke that now all wheelhouses should carry a sextant in a glass case mounted on the wall with a note saying "If lost break glass".
We were talking in the office last week about about the height of the sugarloaf and someone said better get the sextant out. Which was a lot better than saying look it up on google.
posted by adamvasco at 6:23 PM on October 17, 2015 [14 favorites]


You know, it should actually be possible to turn an iPhone into a sextant. It has a very accurate clock, and a camera. If you took a photo of the sun over the horizon at a fixed focal length you would know its ascension.
posted by Joe in Australia at 6:37 PM on October 17, 2015 [6 favorites]


Wasn't there a study that showed that every 7 minutes a seaman thinks of sextants?
posted by clvrmnky at 6:50 PM on October 17, 2015 [11 favorites]


Y'all should watch All Is Lost. It's like The Martian except in a boat in the ocean and there's no help from NASA. (Spoiler: Sextant cameo)
posted by gwint at 6:57 PM on October 17, 2015 [3 favorites]


My dad loves to tell the story of navigating a sailboat through Block Island Sound (Connecticut area) at night, sailing by the stars and the channel buoys, and his sailing buddy below deck waking up and freaking out that the GPS showed them as having run aground...

I think this is an excellent idea for naval officers to know how to sail without electronic gear. "About time they brought that shit back again!" as one of my friends said.
posted by gemmy at 7:28 PM on October 17, 2015 [2 favorites]


I know of more than one USAF aircraft that have had Time Compliance Technical Orders (TCTOs) to remove the sextants on their respective transport-style aircraft.
posted by Quonab at 7:50 PM on October 17, 2015


I was quite angry when I learned they were getting rid of LORAN, and are now getting rid of most of the aircraft navaid stations... this is nuts.
posted by MikeWarot at 7:58 PM on October 17, 2015 [2 favorites]


This reminds me of that "Millennium Challange 2002" where the Red team rocked the Blue team by using analog technology that the Blue team's fancy new tech couldn't intercept or mess with.
posted by Navelgazer at 8:39 PM on October 17, 2015 [1 favorite]


You know, it should actually be possible to turn an iPhone into a sextant.

In fact, if you had a fixed mounting, an iPhone is all you need to navigate to the moon. The camera can spot stars to correct any drift in the accelerometers. You just need a fixed direction to image from to make sure you're seeing the same axis time and time again.

Now, I don't know if there's an app for that, but it's a simple matter of programming, and I don't mean that in the sarcastic sense. The iPhone has everything you need to make it work.
posted by eriko at 8:55 PM on October 17, 2015 [3 favorites]


I'm glad of this ... I remember being lightly outraged when the naval academy did away with celestial navigation as if anyone is going to need an idiot proof low tech backup system to use in case of war or catastrophe, its obviously the Navy!

I also think that many skills are most easily learned by learning the historical problem solving that got to the First Good Solution and how the First Good Solution worked, and how we progress from there to our fancy modern methods. You not only get the basic skills of the First Good Method, but you understand the underlying problem a lot better and the path dependency of the modern methods.
posted by Eyebrows McGee at 10:08 PM on October 17, 2015 [8 favorites]


Not to mention, a proper paper map—an object which costs about $10 and unfolds to several square feet—will always give you a much better idea of what the land around you looks like than the shitty 2.5" screen and crappy, expensive charts of a trail GPS.

If you're doing backwoods hiking, please take the time to laminate your map. Because nobody wants to try figuring out where they are on a soggy mass of pulp that used to be paper.
posted by scalefree at 11:28 PM on October 17, 2015 [1 favorite]


Celestial Navigation for Yachstmen is the book that I see recommended again and again for learning this material in a concise and relatively easy manner.
posted by namewithoutwords at 2:15 AM on October 18, 2015 [2 favorites]


About fucking time. When I heard the Navy was ditching celestial nav, I was like, "WTF?!".
posted by mikelieman at 2:30 AM on October 18, 2015


I sort of have a hunch the Naval Academy stopped teaching celestial navigation in the late 1990s.

1998. "The review committee decided the required sophomore course on navigating by stars was outdated. Then-Superintendent Adm. Charles Larson, after consulting with commanders of Navy ships, cut the course and added extra lessons on computer navigation." More.
posted by MonkeyToes at 6:51 AM on October 18, 2015


For navigation, you want Bowditch, more properly known as The American Practical Navigator. There's a lot more to navigating the seas than getting your current position. Chapter 16 starts the part that talks about celestial navigation.
posted by eriko at 7:22 AM on October 18, 2015 [3 favorites]


An ex-Royal Navy friend of mine was an expert on navigation - in his industry career, he did the initial orbital calculations on the Giotto comet interception mission - and also wrote extensively on the subject practically to the day he died. His study was equipped with all the latest navaids as they came out (he reviewed them for yachting magazines and moved them indoors when he'd finished sailing them about the place), and he took great delight in showing me his house drift gently up the hill as the sun set and the ionosphere mangled the radio waves. He was very, very clear on the importance of knowing celestial navigation, because he KNEW how dangerous space was for electronics.

Plus, he was obviously right. I would no more think of setting off on a serious bit of walking without map and compass than I would without my trousers. It works, plus it enriches your appreciation of the landscape in so many ways. It is possible, with experience and preparation, to ensure you just do not get lost no matter what happens to you. Even in the worst weather, provided you can still walk the ground beneath your feet will tell you enough - provided you have your map and compass. Neither will ever die before you do.

However, I never got to ask my friend about the idea to combine the best aspects of electronic and celestial navigation by using pulsars as reference points. Sure, there are a few technicalities to sort out, but details, details.

(He was also a world-class bullshitter with a world-class bullshitter's ability to detect bullshit, something a career as a senior RN officer will equip you with. He also had absolutely no patience with woo merchants or anyone who used the phrase "You scientists..." If confronted with such, he'd offer to recite the Shakespeare sonnet of their choice from memory if his interlocutor would do the same with the three laws of thermodynamics.

"Do you actually know all the sonnets?" I asked.

"Never had to find out", he said. "Another gin?")
posted by Devonian at 7:24 AM on October 18, 2015 [17 favorites]


Thanks Devonian! My dad had a friend named Oakley-Evans who was a retired RN officer, and was full of... amazing stories about life in the upper echelons, being a wealthy guy in Europe in the 50's, and stories about British India. "Best swordsman in the RN!" etc. He made a big impression on me, although we never heard about any feats of navigation.
posted by sneebler at 8:47 AM on October 18, 2015


If they stopped teaching this in 1998 then I was in one of the last classes to whom they taught this skill. Maybe my instructor sucked but we didn't even touch a sextant or learn how to make the observations; I think the working assumption, aside from an unspoken one that we'd never really need to do this, was that we could just rely on our enlisted personnel to make the observations and supply us with the numbers we needed. We just learned how to perform the lookups and calculations (are there any calculations? It's been a few years...) using the big stack of books with tables of numbers. It was very much a stupid exercise in futility.
posted by ElKevbo at 8:57 AM on October 18, 2015


My friend died about thirty years ago, Sneebler, but I still miss him terribly. He was such good company. I could go on about him for ages - his life was one of the ones you read about in the Daily Telegraph military obituaries and can't quite believe - but two more facts that I can't resist before I finish this derail. He was an officer in the Royal Yacht Squadron and good friends with the Duke of Edinburgh, whom he adored (they were cut from the same cloth), and he worked 'in radar' during the war with Arthur Clarke, whom he most certainly did not.

I was too young to really appreciate him. You know you're not supposed to have regrets in life? Hey ho.
posted by Devonian at 12:06 PM on October 18, 2015 [2 favorites]


This was my job for more than ten years in the Navy. I am not even sure I should start typing, for fear I can't stop. I was there when they decided to stop teaching celestial navigation to enlisted quartermasters (2001). And I was there for the end of the transition to fully electronic navigation-- not even paper charts on the chart table on the bridge any more.

But mostly I was there for the nightmarish decade-long transition where we had to do both jobs (paper navigation and electronic navigation) at the same time-- more than doubling our workload while continuously slashing manpower. It injured my body and soul in a way that my previous four years as US Army infantryman never did. But enough of my sob story.

Celestial navigation is tediously complicated in a fiddly way that "digital natives" have a hard time assimilating. There are numerous edge-case instructions like "invert this denominator if you are above 70 degrees north latitude" that are not explained or even noted in many reference books, but must be passed down orally in the style of an 18th century blacksmith. It takes a huge amount of training to be good at it, although there are a few easy things to do in "a day's work in navigation" that lend themselves to teaching-- the noon sight, computing sunrise and sunset, etc.

All of this had to be taught to 18 and 19-year-old kids who joined the Navy because they absolutely did not want to go to college and learn a bunch of geography, oceanography and spherical trigonometry. It all has to fit in with a punishing watchstanding schedule that only sees you getting a full night's sleep one in three nights, and it all has to be fit into what officers think is the really critical mission of enlisted watchstanders on the Bridge: Janitorial work and painting the bridge wings.

For all of this most real-world calculations of selected stars will only bring you within 60 or so miles of where you are. In the days of the sailing ships they used it as a warning to tell them when they were approaching land, and to when to post extra lookouts to check for lighthouses and other features. For a generation used to the 82-foot cone of accuracy of modern GPS, it is a hard sell.

For all that it is absolutely essential to have these skills as a backup. It was jaw-grindingly stupid of the Navy to think they could get away without it, and I am glad to see it come back. Printed on every single chart is the phrase "The prudent mariner will not rely on any one single means of navigation." I guess the higher-ups are starting to realize it is true.
posted by seasparrow at 8:23 AM on October 19, 2015 [7 favorites]


sextant iphone app

Considering most smartphones have a camera, accelerator, and compass, shouldn't it be easy to write a celestial navigation app using OpenCV or similar? Then again, not sure smartphone cameras would get a great view of the stars on all but the darkest and clearest nights.
posted by mccarty.tim at 9:26 AM on October 19, 2015


There are at least a couple of Android apps that claim to work like a sextant and compass.
Sextant
StarStruck
posted by Kirth Gerson at 12:50 PM on October 19, 2015


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