Would appreciate your thoughts about using the sun to navigate by.

Sample scenario: You are in the back country and the magnetic compass is destroyed. You have no GPS.

I am looking for a few time tested methods/techniques for a future lesson plan.

My references that I use include the books Staying Found, US Army Field Manual FM 21-76.

Thanks in advance,

Blake

www.outdoorquest.blogspot.com

If I know the time of day and the sun is visible but is not high overhead, it's pretty easy to determine East or West and rough out your other directions. You can also use an analog watch as a compass:



As with any map and compass exercise, once I'm oriented and I can orient the map I will try to associate terrain features with the map to make sure that I'm seeing what I think I'm seeing.

There is the shadow tip method.

I always loved that trick but keep forgetting how it works.

I assume you use standard time (not daylight saving).

I wonder: if you have a digital watch (or phone) set to local time, would it work to scratch a clock face and hour hand in the dirt?

This device doubles as watch and compass:
Pocket sun dial
When using the watch method described by chaosmagnet, don´t forget that during daylight saving time the angle to divide is between the hour hand and the 1 o´clock mark. The method is not overly precise but it is better than nothing. So use it to find a long range target and go for that.

True, but test it before relying on it. I was discouraged to find that there was a substantial error factor. Maybe it's a higher lattitude issue? I dunno.

For best results use true local time. Everything else might need correction.


It sure does. With a piece of string you may even get the hour marks fairly precise.

It is a combination of lattitude, time of day (it´s good around high noon) and time of year. You may get up to 30 or 40 degrees of systematic error (that is without fouling anything up). Just take a look at the face of a sun dial and you get an idea of it.

We discussed this in another thread a few months back. Ottomani Sun compass

true ... it was discussed before.

my own answer is that it can be done quite accurately these days.
the reason is that there are computer programs and online sites that allow you to get the sun's position at any time of day - and for any lat and long. as a result, you can make a short list of the sun directions at various times, and bingo you've got automatic direction finding. certainly accurate to 5 degrees, and you could probably do better if you worked on it.

of course ... you do need a sunny day :-)

good luck.
Pete2

I've got an App on my cellphone that will tell me where the sun is -- Celestial by Navimatics, but then the phone has a built in electronic compass too and then there's Sun Compass for iPad, iPod Touch and iPhone

I think the idea of this thread's exercise is determine direction without tech -- no compass, no watch, no cheat sheet with sun directions, no iPhone ... A simple stick in the ground and tracking the sun's shadow and you can have a fairly accurate idea of N-S-E-W. With a little time you can make a sun compass that travels with you. Simple no-tech solutions.

Navigation by the sun is easy to learn and one can obtain an accurate N/S/E/W direction when using the stick method. Over the years I have shown many people this method and they were not aware of and have been surprised of this primitive but very effective way of direction finding.

As for the watch method, even with the digital watches, we all should still have a good idea where the old analog numbers would be located on a modern digital watch. You are then still able to obtain a very good indicator of N/S/E/W direction without any difficulty.

Needless to say though, having a compass (and a backup compass) pays dividends for times where the sun is blocked by cloud, rain or snow which can last for hours, if not days depending on where you are.

Yes it works

I am familiar with the sun compass process with the large stick. I put that together Sunday and it works quite well.

The larger the stick the better.

I'll check out the video again.

Izzy, thanks for the input regarding using your watch.

Blake

Teslinhiker - just how accurate do you think this method is? I think the process is great.

Blake

www.outdoorquest.blogspot.com

On a sunny day and with a tall enough stick, it should be dead-on. At local apparent noon, the stick's shortest shadow should be pointed straight to true north. Given a long enough timeframe to lay out a line of stakes, the line should form a straight E-W line.

Do this as a test when you still have a compass to check it, this will give you the confidence to trust it. Personally, I would use this technique to check the compass, rather than using a compass to check the sun. Don't forget to account for magnetic deviation -- the sun compass is True.

As Russ mentioned, the accuracy of the method is dead on. However like any direction finding, it requires skill to keep headed in the right direction, especially in unfamiliar, featureless or dense terrain. Some people will initially get themselves headed in the right direction but will soon deviate as they start off with the sun on one shoulder, to their back, or their front. It might not occur to them that the sun is still moving through the sky but they keep with the original thought that N/S/E/W "must be that way" because that is where the sun was on their body when they stopped to find their initial direction.

Even in as a little as 1/2 hour, you can be degrees away from your original, targeted direction enough to miss that crucial trail junction, trailhead, water stream etc.

This same principle applies to using a compass. For example; if you look orient your compass to North then deviate 5 -10 degrees away from North, it does not look like much at a short distance, however over a much longer distance, you can be far enough off direction from your destination that you may not notice and miss that trail junction etc by a fair amount if you do not take the time to take compass readings as you go.

That is why when you take a compass bearing you should find a landmark in that direction and hike toward that rather than just walking in that direction. People in general do not walk a straight line unless they have a target.

Also, the Ottamani compass can be carried and the sun's shadow marked with time of day. As you walk, orient the compass so the shadow is cast where it should be at that time, compass direction should be close. $.02 (never had to try that)

That works if the daylight skies are clear and also without your visible terrain features being obscured by falling darkness, heavy fog, falling/blowing snow etc.

Found this short tutorial on Youtube. This young man aptly demonstrates the basic concepts of the stick compass method.

Well, since you guys are so utterly adamant, I'll give it another try in more controlled conditions. And with a bigger stick.

I have come across other references that line up with M_a_x's thoughts (and with my initial, admittedly crude experiments). These don't invalidate the technique in any way, they simply note variations that creep in based on time of day, lattitude, and season. This, I assume, is celestial mechanics doing what it has always done.

If it works best around noon, I'll start with that. And then I'll try to get a sense of early/late results, and what kind of correction factor I should keep in mind. I don't mind that at all, provided I know what to adjust for. It's in the same vein as compass declination, which for the record I have been adjusting for long before I started posting on ETS.

I do most of my navigation while hiking via the sun, but there are times when the clouds are out and I just can't see it.

Look at it this way. At 6 am, the sun is more or less in the east. At noon it is due south. at 6 pm it is more or less due west. use standard time.

If it is 3 pm, the sun will be in thw SW. At 9 am in the NE.

It is not perfect but has always been close enough for me to navigate from a trail map.

While in Greenland I was trained to use a polarizing filter to judge the suns location when the sky was obscured by fog or clouds. Worked well. I wonder if it would work with polarized sun glasses? I will have to give it a try. I am in sunny southwest now so it will have to wait awhile.

Compasses were useless most of the time as we were well above the magnetic pole and the earths electrical field was a real mess. Compass would just spin.

I can't remember all the details of the solar polarizing compass. Perhaps there is information on the net.

Nomad.

This has worked for me in the past. If the cloud cover is very thick it can be problematic.

The sun compass was designed in the 1830's for work where the magnetic compass failed (work in Wisconson near the iron ore brought about the invention). They were common in arctic exploration till at least the 1980's. The fancy ones had a precision clock movement (like a mariners chronometer) so that they could be read without movement. Most had a dial that was turned to set the time from a chronometer or radio signal (you got good at listing to WWV). They worked whenever you could tell the position of the sun.

The polarizing sun compass was developed by SAS (the airlines) in the 1950's to allow navigation during twilight and can be used to some degree during cloudy weather. The polarizing compass works on the principle that light from the sun is polarized at right angles to the line toward the sun when you look directly overhead. That angle will give you a line toward the sun and with a time hack direction like a sun compass. See: http://www2.gi.alaska.edu/ScienceForum/ASF8/865.html

Respectfully,

Jerry

Sorry that this has nothing to do with the sun, but it has to do with navigation , and improvisation (which I love)

http://www.youtube.com/watch?v=xqg60fJQuQM