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Old Boy Scout trick... using your watch as a compass.

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posted on Aug, 5 2011 @ 09:33 AM
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but to do this you need an old school analog watch... if ya got $700 for the one above cool... but your cheap walmart special will work too...

It's possible to determine your orientation using an analog watch (i.e., one with hands) in place of a compass. The direction will be correct if the watch is set for true local time, without adjustments for daylight savings time. And the further you are from the equator, the more accurate this method will be.


In the northern hemisphere, hold the watch horizontal and point the hour hand in the direction of the sun. Bisect the angle between the hour hand and the twelve o'clock mark to get the north-south line. North will be the direction further from the sun.


In the southern hemisphere, hold the watch horizontal and point the twelve o'clock mark in the direction of the sun. Bisect the angle between the hour hand and the twelve o'clock mark to get the north-south line. North will be the direction closer to the sun.

You say you don't have one of these old time watches... no prob... as long as you know what time it is A simple drawing of a watch on a piece of paper, as long as it shows the correct time (you only need worry about the hour hand), works just as well.

Can't see the sun clearly, or otherwise having difficulty determining its direction? As long as the sun is able to cast a shadow (which it can often do even through fog), you can determine its direction by holding a thin object (like a pencil or a stick) straight up and down; the resulting shadow will point away from the sun.

Wonder why you're bisecting angles? As the earth rotates once (each day), the hour hand goes around the clock face twice. So you need to divide the angle by two (i.e., in half).

One you figure out which way is north you can then make yourself a sundial just as a fun project to do with the kids Place to get direction on making sundials




posted on Aug, 5 2011 @ 09:43 AM
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I forgot all about this....Thanks for the refresher daddybare! To think I spent the extra ching, and bought an analog watch w/ integrated compass, when all I needed to do was point my hour hand at the sun. Damn you memory, now your costing me money!



posted on Aug, 5 2011 @ 09:58 AM
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I should add Telling time by the stars is not really very useful.... but if ya want to be really hard core...

Really this is way crazy Comp-lu-ma-kated... but I know someone is bound to ask...

Anyway, here is how I do it. This is just a quick overview; you will have to fill in many details on your own. Also note that tradeoffs have been made between convenience and accuracy: there are simpler methods that are grossly inaccurate, and more-accurate methods that are more complex (using equatorial rather than circumpolar stars).

1. Memorize four landmarks (skymarks?) ◦ The 0-hour circle. This is marked by Beta Cassiopeiae (Caph) which is the star at the bright end of the famous W in the constellation Cassiopeia, i.e. the end with the acute angle. Continuing along the 0-hour circle, we come to Alpha Andromedae (Alpheratz) and Gamma Pegasi (Algenib) which together constitute the trailing (eastern) edge of the Great Square – hard to miss.
◦The 6-hour circle. This is marked by Delta Aurigae, Beta Aurigae (Menkalinan), and Theta Aurigae.
◦The 12-hour circle. This is marked by point halfway between Delta and Gamma Ursae Majoris, the two non-pointer stars in the bowl of the Big Dipper. (The pointer stars are excellent markers for the 11-hour circle.)
◦The 18-hour circle. This is marked by Chi, Phi, Xi, and Gamma Draconis, i.e. the hind feet, chin, and nose (Eltanin) of the Dragon.

Also remember that the 12-hour circle is the continuation of the 0-hour circle, and that the 18-hour circle is the continuation of the 6-hour circle.

2.Remember that the 12-hour circle is overhead at midnight at the spring equinox. The 18-hour circle is overhead 6 hours later, and/or 3 months later in the year. And so forth. This gives you four “primary” reference pictures, where one of these four circles is overhead.

3.You can then construct four “secondary” reference pictures, halfway between the primaries. These correspond to the situation where the primary circles form a giant V shape that is symmetrical with respect to the vertical. Do not try to judge the angle that the circles form relative to horizontal, because the perception of horizontal is distorted by the spherical geometry. The perception of vertical is OK, and the perception of symmetry is OK. Anything else you need can be judged by interpolation between the symmetrical (secondary) picture and the vertical (primary) picture.

4.As you face north, the great clock in the sky rotates counterclockwise.1,2 It moves counterclockwise as you get later in the night or later in the year. The time-of-year contribution is 2 hours per month, or half an hour per week, or four minutes per day.

5.Therefore: Suppose it is March 22nd. If you see the 12-hour circle is past vertical, 1/3rd of the way to the symmetrical V position, it must be 1:00 AM. If it is two weeks later in the year, the same picture is 12:00 midnight (standard time); the advancement is explained by being later in the year, not later at night.

6.Correct for daylight savings time. If DST is in effect, official time is one hour later than star time.

7.Correct for longitude. ◦To a rough first approximation, time zones are 1 hour wide, and the standard time in each zone more-or-less corresponds to the mean solar time at the middle of the zone. Therefore, roughly speaking, if you are near the edge of a zone, standard time could be offset by half an hour from the local mean solar time.

◦In reality, things are much more complicated than that. Time zone boundaries follow political boundaries, not the ideal theoretical lines of longitude. Useful diagrams can be found in reference 1. You can easily find places (such as western Spain) where the standard time is offset by more than 1.5 hours from the local mean solar time. That is, the zone extends more than 1.5 hours from where the middle of the zone “should” ideally be.

If you are west of the nominal midline of your time zone, official time is later than star time. By the same token, if you are east of the midline, official time is earlier than star time.



posted on Aug, 5 2011 @ 12:28 PM
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reply to post by DaddyBare
 


Very interesting indeed.

Hopefully someday I wont have to use it but wish I can memorise all of it



posted on Aug, 5 2011 @ 12:33 PM
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S&F. Your posts are unbelievably educational. Thanks



posted on Aug, 5 2011 @ 02:02 PM
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reply to post by blackmetalmist
 


I wish I could take credit for this...
truth is... not so long ago every boy was taught these things...
of course that was before we had Cell phones WiFi and GPS...

If anything my so called wisdom comes from growing up in a different age...
There are things I am glad to see go... but others... like this handy dandy trick... should never have been allowed to die out

edit on 5-8-2011 by DaddyBare because: (no reason given)



posted on Aug, 5 2011 @ 02:21 PM
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There's an easier way that works with all watches. If it's before noon, turn so the sun is on your right. If it's after noon, turn so the sun is on your left. You'll be facing north either way.



posted on Aug, 5 2011 @ 02:27 PM
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I spent three years in the cub and boy scouts. I completely forgot about this! Thanks for the refresher Daddybear! SnF for you!



posted on Aug, 5 2011 @ 02:37 PM
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Originally posted by N3k9Ni
There's an easier way that works with all watches. If it's before noon, turn so the sun is on your right. If it's after noon, turn so the sun is on your left. You'll be facing north either way.


There's yet another way...
here in the US...
all highways that run west and east will end with an even number.. interstate 10, 40, 44, 70, 80....
Highways that run north and south will always end with an odd number Pacific coast 101, interstate 15, 19 25 etc, etc etc...

so as long as you can read the number on a highway sign you know




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