That works the best close to noon, but I don’t think that works so well at around dawn or dusk.
Latitude also matters. The closer it is to the arctic or antarctic circle, the iffier that gets.
This isn’t a trick so much as just how the sun and the earth defines the plane of the ecliptic and how we experience it because of Earth’s rotation.
There are some interesting things that can be done with starlight navigation. The Polynesans, for example, might navigate by latitude based on how far up Sirius is in the sky, or using the little dipper (and Polaris) in the Northern Hemisphere as a clock.
The shadow is always going to be opposite of the sun, so it does not provide any extra info which the sun doesn't already give you.
In order to estimate the current time ("it's about 5 o'clock") using the position of the sun/a shadow - you need to know the cardinal directions. So, only if you already know where north is, you can tell the time from the shadow.
In order to estimate the cardinal directions from the position of the sun/a shadow - you need to know what time it is. So only if you know the time, you can tell where north is from the sun/shadow. And to know the time you need a watch or something similar?
But if you can deduce both time AND cardinal directions just using the sun/shadow and no other information... yeah, I have to agree, that seems like witchcraft!
> The sun is over there, a shadow would be that way, it's about 5 o'clock. That must be north!
That works for example if you have a path and you're trying to find out which way goes north and which south, but a watch can give you an actual quantifiable bearing that is actionable if you have no other ground orientation.
Or, if you’re in the Pacific Northwest and mistake the diffuse daylight for direct sunshine, you’ve probably started tracking crow movements by accident.
Isn't this incorrect? If it's summer, south of the Tropic of Cancer, the stick should be North of the line. It's the Tropic of Cancer where the sun is overhead, not at the equator. Or did I understand basic astrophysics wrong.
Similarly, in the winters, I'd imagine North of the Tropic of Capricorn would play the role of the Tropic of Cancer.
I have a wonderful book called the “Rudge Book of the Road” from the 1920s that’s full of stuff like this.
It was written as a companion for Rudge-Whitworth motorcycles and tells you how to determine direction of travel by looking at trees among other things.
From some of the comments, I’m not sure people fully get this. It’s basically doing a geometric construction of the sun’s path across the sky, using the distance between the hour hand and the 12 on the watch face as one of the input angles in the calculation. That’s quick (important because you have to repeat it while you’re marching) and easy to remember (also important because you might need it in a situation without access to Wikipedia). Under the assumption that the sun rises at 06:00 in the exact East and sets at 18:00 in the exact West, the construction is almost perfect. Of course, that’s never exactly true in real life, but still a lot more accurate than “well I know the sun is roughly South”.
> That’s quick (important because you have to repeat it while you’re marching) and easy to remember (also important because you might need it in a situation without access to Wikipedia).
I was taught this as a child, which was very accessible, felt incredibly magical yet made total sense, and super empowering.
I grew up in an hilly area with lots of forest, where intuitively orienting yourself can be hard in itself, doubly so consistently over even a short walk.
However imperfect, this technique allows one to consistently and unambiguously orient themselves via an absolute measurement subject to an error margin but impervious to error accumulation, and, when lost, not end up exhausting themselves to death by walking in circles.
Knowing that (plus orienting myself with stars at night, and a couple of other safety+emergency tricks) is probably why my parents allowed me to roam around freely by myself without anything like a cell phone (at the time they were at best an oddity that you saw in Hollywood movies), even at a very young age!
Most parents these day would probably pass out at mere the idea of a lone 12yo taking on a hike by themselves in such a way. For me it resulted in the complete vanishing of the fear of being lost; instead exploring by "getting lost" became the most thrilling activity ever.
Australian checking in. for the second time this week I'm commenting that your US/Northern Hemisphere sun goes THE WRONG WAY for my internal navigation instincts...
At around noon, when the Sun reaches the zenith (at least of you are not in the polar regions), it would be South in the Northern Hemisphere and North in the Southern Hemisphere. At that point, east-west axis is easier to establish. Doing this other than noon is going to get more distortions, based upon time of year and latitude. It’ll probably be reasonably accurate if someone is in the equatorial belt.
The equinoxes are the times when that east-west is going to be east west.
Thinking about this, this is probably how the clock and the sextant lets people navigate on the open ocean during the age of sail.
I love this trick. You can also do this using your hands if you know roughly what time it is.
For example, if it's sunny out, place your arm in your shadow, parallel to the ground. Keep it there. This arm represents the current time (say, 10 O'clock).
Look at your shadow and point your other arm out, parallel to the ground, and adjust it until the arm's shadow points at "12 O'clock" relative to your first arm (in your shadow).
Clap your hands together, and you're pointing north!
Imagine (for simplicity) that we have 6a to 6p with solar noon at 12p.
Then if I put my right arm in my shadow at 6am and my other arm 180 degrees from it, then I’ll be facing South. If I do the same thing at 11 am, I form a big wedge with my right arm on the NW side, again facing South.
But at noon that changes: the sun is directly South from me, so my right arm is North and my other arm is in the same spot, so I turn around to face North.
From there, my right arm is on the NE side, and my left arm makes a widening wedge as I face North — until at 6pm, I’m standing with my right arm facing East and my left arm opposite it, facing North.
Southern Hemisphere version: Instead of pointing the hour hand at the sun, point the twelve o'clock at the sun. North is approximately half way between the hour hand and the 12.
Very impressive reaction from the guy in the video, but I don't think he's using this to tell the heading. It looks like he also has a compass on his watch band as you can see at 1:03.
Of course what you describe is the main way people navigate by the sun, when the margin of error is bearable. In more extreme situations where precision is needed, decimating the margin of error is pretty important, especially when used in conjunction with a map or known landmarks.
Isn't this just using the sun as a compass? You could easily just look at the position of the sun knowing what time it is, or use your hand and make a sun-dial. I believe the watch is only there to tell us the time and cross reference that with the sun's position.
Yeah, the strategy only really involves (A) knowing the current time and (B) a protractor or a good sense of angles.
Or in word-algorithm form:
1. When the sun rises that's usually at 6AM in the East, at 12AM noon it's usually towards the South, and when it sets that's usually 6PM in the west. (Valid for northern hemisphere only.)
2. Use the current time to linearly interpolate between those three values.
3. Once you know the heading of the sun, you can figure out which way is north.
Essentially this means approximating the bearing of the sun X hours after midnight the sun as 15X degrees. This works better the closer to the poles you are and the closer to the winter solstice it is - see for example https://possiblywrong.wordpress.com/2012/01/25/using-a-watch...
I learned this from Gallipoli (1981 Peter Weir movie about WW1). In the movie they get totally screwed by this trick when it turns out it’s overcast.
Tangent, that movie is great, the synthesizer music is odd but to me it works and the whole movie is beautiful.
I've been to-and-fro across much of North America for much of my life. I have never encountered a situation where it was especially challenging to orient to the cardinal directions in a few minutes using a few basic clues; how trees and plants orient, satellite dishes, how houses are oriented, the stars, the time of year and the subsequent location of the sun, how streets are planned, named & numbered. Even a cursory glance at a map can help you identify major terrain features that can help you orient.
Have never had to resort to these methods of using a watch or a magnetized needle, because waking up in in the middle of a mysterious jungle is a pretty rare event ;)
>I've been to-and-fro across much of North America for much of my life. I have never encountered a situation where it was especially challenging to orient to the cardinal directions...
This is one thing I always find quite odd on American TV / Films.
People [eg. police pursuing someone] will inevtiably say something like "He's turned north onto 21st St." or "He's heading east on 12th street". I always wonder how they know the compass direction. I don't think many people in Britain would express directions like this, using compass points, or even know which direction was which.
Do US streets have the cardinal directions on the roadsigns, or are you all issued with built-in compasses at birth?
It's a shame really that most watches are 12 hour time. With a 24 hour clock (with noon at the top/midnight at the bottom) the hour hand tracks the Sun and North is at 12. And it's obvious enough that you don't even need to remember how it works.
In the Southern Hemisphere you need a clock that goes anti-clockwise (or you can mentally flip it).
This is a very cool use for a watch. You can use any watch, but some watches, like the Seiko Alpinist, even have a rotating bezel with the compass points. This makes it a lot easier to find the other directions. One thing the article forgot to mention, is that the trick works only for standard time. If you are on daylight savings time, the direction will be off.
Depends: are you the kind of person who considers it a good idea to be aware of uncertainty? You'll be perfectly happy with "I'm on the northern hemisphere, it's afternoon, so south must be somewhere left of the sun".
But if you are the kind of person who like to lose themselves in point-something percentage point deltas in small (or unknown) sample size market research, go on, pat yourself on the shoulder for building that makeshift shadow observatory, it will make you happy even if you don't really know where exactly you are relative to the center and natural bounds of you time zone.
[+] [-] psychphysic|3 years ago|reply
The sun is over there, a shadow would be that way, it's about 5 o'clock. That must be north!
What I've always thought of as witchcraft is this.
Jab a stick in the ground, mark the end of the shadow. Come back some time later say 15-30mins. Mark the new end of the shadow.
Draw a line between marks and that is an east-west line!
In the Northern hemisphere the stick is south of that line, in the southern hemisphere it's North!
What!!
[+] [-] hosh|3 years ago|reply
Latitude also matters. The closer it is to the arctic or antarctic circle, the iffier that gets.
This isn’t a trick so much as just how the sun and the earth defines the plane of the ecliptic and how we experience it because of Earth’s rotation.
There are some interesting things that can be done with starlight navigation. The Polynesans, for example, might navigate by latitude based on how far up Sirius is in the sky, or using the little dipper (and Polaris) in the Northern Hemisphere as a clock.
[+] [-] Normille|3 years ago|reply
[+] [-] CSSer|3 years ago|reply
[+] [-] hooby|3 years ago|reply
The shadow is always going to be opposite of the sun, so it does not provide any extra info which the sun doesn't already give you.
In order to estimate the current time ("it's about 5 o'clock") using the position of the sun/a shadow - you need to know the cardinal directions. So, only if you already know where north is, you can tell the time from the shadow.
In order to estimate the cardinal directions from the position of the sun/a shadow - you need to know what time it is. So only if you know the time, you can tell where north is from the sun/shadow. And to know the time you need a watch or something similar?
But if you can deduce both time AND cardinal directions just using the sun/shadow and no other information... yeah, I have to agree, that seems like witchcraft!
[+] [-] grecy|3 years ago|reply
I highly recommend spending 12 months way up north to have your mind constantly blown by the path of the sun. Every year it’s still a shock to watch.
[+] [-] chrisseaton|3 years ago|reply
That works for example if you have a path and you're trying to find out which way goes north and which south, but a watch can give you an actual quantifiable bearing that is actionable if you have no other ground orientation.
[+] [-] zikduruqe|3 years ago|reply
https://thankfulslave.blogspot.com/2012/06/sun-compass-ottom...
And read The Natural Navigator by Tristan Gooley. You will be amazed at what you can use to navigate when you can read the signs.
https://www.naturalnavigator.com/tristan-gooley/
[+] [-] eyelidlessness|3 years ago|reply
[+] [-] helmholtz|3 years ago|reply
Similarly, in the winters, I'd imagine North of the Tropic of Capricorn would play the role of the Tropic of Cancer.
[+] [-] shever73|3 years ago|reply
It was written as a companion for Rudge-Whitworth motorcycles and tells you how to determine direction of travel by looking at trees among other things.
[+] [-] codeflo|3 years ago|reply
[+] [-] lloeki|3 years ago|reply
I was taught this as a child, which was very accessible, felt incredibly magical yet made total sense, and super empowering.
I grew up in an hilly area with lots of forest, where intuitively orienting yourself can be hard in itself, doubly so consistently over even a short walk.
However imperfect, this technique allows one to consistently and unambiguously orient themselves via an absolute measurement subject to an error margin but impervious to error accumulation, and, when lost, not end up exhausting themselves to death by walking in circles.
Knowing that (plus orienting myself with stars at night, and a couple of other safety+emergency tricks) is probably why my parents allowed me to roam around freely by myself without anything like a cell phone (at the time they were at best an oddity that you saw in Hollywood movies), even at a very young age!
Most parents these day would probably pass out at mere the idea of a lone 12yo taking on a hike by themselves in such a way. For me it resulted in the complete vanishing of the fear of being lost; instead exploring by "getting lost" became the most thrilling activity ever.
[+] [-] bigiain|3 years ago|reply
The sun is currently about NNE as I write this.
[+] [-] hosh|3 years ago|reply
The equinoxes are the times when that east-west is going to be east west.
Thinking about this, this is probably how the clock and the sextant lets people navigate on the open ocean during the age of sail.
[+] [-] dheera|3 years ago|reply
[+] [-] kije|3 years ago|reply
For example, if it's sunny out, place your arm in your shadow, parallel to the ground. Keep it there. This arm represents the current time (say, 10 O'clock). Look at your shadow and point your other arm out, parallel to the ground, and adjust it until the arm's shadow points at "12 O'clock" relative to your first arm (in your shadow). Clap your hands together, and you're pointing north!
[+] [-] zmgsabst|3 years ago|reply
Imagine (for simplicity) that we have 6a to 6p with solar noon at 12p.
Then if I put my right arm in my shadow at 6am and my other arm 180 degrees from it, then I’ll be facing South. If I do the same thing at 11 am, I form a big wedge with my right arm on the NW side, again facing South.
But at noon that changes: the sun is directly South from me, so my right arm is North and my other arm is in the same spot, so I turn around to face North.
From there, my right arm is on the NE side, and my left arm makes a widening wedge as I face North — until at 6pm, I’m standing with my right arm facing East and my left arm opposite it, facing North.
[+] [-] soperj|3 years ago|reply
[+] [-] Nition|3 years ago|reply
[+] [-] gowld|3 years ago|reply
[+] [-] est|3 years ago|reply
1. In a perfect world, 12 o' clock is where sun at its highest peak in the sky, 24 o' clock is where sun below the horizon at its lowest.
2. If your are in northern hemisphere, the sun's trajectory is slightly off to the south.
Now try emulate the sun's rotation with your watch's hour hand.
[+] [-] vesinisa|3 years ago|reply
[+] [-] TheRealPomax|3 years ago|reply
[+] [-] Ylpertnodi|3 years ago|reply
https://www.reddit.com/r/UkraineWarVideoReport/comments/u79d...
about 38 seconds in.
[+] [-] lostsock|3 years ago|reply
[+] [-] re|3 years ago|reply
[+] [-] madcaptenor|3 years ago|reply
[+] [-] recasfoin|3 years ago|reply
https://academic.oup.com/astrogeo/article/52/3/3.12/187095
[+] [-] quickthrower2|3 years ago|reply
[+] [-] schoen|3 years ago|reply
This is because geostationary orbits (where satellites that communicate with fixed satellite dishes are located) are all above the equator.
https://en.wikipedia.org/wiki/Geostationary_orbit
So, these dishes are aimed at a point above the equator (possibly with some eastward or westward component, but mainly southward).
[+] [-] gonzo|3 years ago|reply
https://mediafiles.scoutshop.org/m2pdf/BePrepared_Vol_3_No_9...
[+] [-] xcambar|3 years ago|reply
It always works significantly well, meaning I never need it on critical situations and the margin of error is bearable.
But I'm mostly surprised not to see someone else comment the technique before. Is it not a known technique?
[+] [-] uoaei|3 years ago|reply
[+] [-] throwaway4837|3 years ago|reply
[+] [-] Terr_|3 years ago|reply
Or in word-algorithm form:
1. When the sun rises that's usually at 6AM in the East, at 12AM noon it's usually towards the South, and when it sets that's usually 6PM in the west. (Valid for northern hemisphere only.)
2. Use the current time to linearly interpolate between those three values.
3. Once you know the heading of the sun, you can figure out which way is north.
[+] [-] rosywoozlechan|3 years ago|reply
[+] [-] nicbou|3 years ago|reply
This gets you a rough idea of where North is. Do it often enough and it becomes instinctual. You keep your bearings so long as the sun is up.
This is useful if you don't want to constantly check your phone.
[+] [-] perilunar|3 years ago|reply
As long as you are north of the Tropic of Cancer.
[+] [-] frankus|3 years ago|reply
[+] [-] madcaptenor|3 years ago|reply
[+] [-] bigmattystyles|3 years ago|reply
[+] [-] 23B1|3 years ago|reply
Have never had to resort to these methods of using a watch or a magnetized needle, because waking up in in the middle of a mysterious jungle is a pretty rare event ;)
[+] [-] Normille|3 years ago|reply
People [eg. police pursuing someone] will inevtiably say something like "He's turned north onto 21st St." or "He's heading east on 12th street". I always wonder how they know the compass direction. I don't think many people in Britain would express directions like this, using compass points, or even know which direction was which.
Do US streets have the cardinal directions on the roadsigns, or are you all issued with built-in compasses at birth?
[+] [-] tmtvl|3 years ago|reply
[+] [-] perilunar|3 years ago|reply
In the Southern Hemisphere you need a clock that goes anti-clockwise (or you can mentally flip it).
See: https://sunclock.net
[+] [-] tolger|3 years ago|reply
[+] [-] system2|3 years ago|reply
[+] [-] usrusr|3 years ago|reply
But if you are the kind of person who like to lose themselves in point-something percentage point deltas in small (or unknown) sample size market research, go on, pat yourself on the shoulder for building that makeshift shadow observatory, it will make you happy even if you don't really know where exactly you are relative to the center and natural bounds of you time zone.
[+] [-] certifiedloud|3 years ago|reply