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  • 3 Post By nolatom
  • 2 Post By Seaduction
  • 3 Post By deniseO30
  • 1 Post By smurphny
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  #1  
Old 08-07-2013
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"Stupid human trick"--estimate bearings without yr compass

So, here's a "stupid Human trick"--estimating degrees of angle w/o instruments

Did you ever want to be able to easily determine approximately how many compass degrees something is from something else?

there's a simple way, no equipment needed (even though yes, you do have a compass I hope).

On average, a fist (with thumb on top, not wrapped around the fingers), on an arm fully extended in front of your eyes, describes an arc of ten degrees, from bottom of pinky finger to top of thumb.

So--is boat A two fists off your headstay? that's 20 degrees. Try doing this with nine fists in succession and you'll see you've made a right angle (90 degrees), whether you are moving horizontally for a terrestrial object, or vertically for a celestial one.

And you can be a latitude-navigator without a sextant. Find the North Star (Big Dipper outer two stars of the spoon point you towards Polaris). Either see (twilight) or estimate your horizontal horizon, and go fist-over fists up to Polaris. Four fists? You're at 40 degrees latitude (Massachusetts!). 3 Fists? New Orleans (I know this one, 30 degrees north of the equator). Latitude navigators discovered the world centuries before they figured out how to find longitude.

How long til sunset (Moonset)? Easy. How many fists from sun down to horizon, or vice-versa? 4 and a half fists? that's 45 degrees. The sun (and all sky objects) "move" at 15 degrees an hour (since Earth rotates 360 of them in 24 hours, si?). So you have 3 hours to finish that dive, or that round of golf. Each fist is worth 10 degrees, so that's 40 minutes of movement. So, if you want cut it closer, each finger/knuckle is worth about 2 degrees, or 8 minutes.

And, a fist is almost 11-1/4 degrees, which is a "Point" forus sailors and historians ("Land ho, 3 points off the port bow!!" a point being 360 degrees divided by 32, if you've ever "boxed" the compass). Now you know what they're talking about in "Moby Dick" and such.

So the human trick ain't so stupid, eh? (hey, trust me, I'm an English Major)
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Last edited by nolatom; 08-07-2013 at 11:35 AM.
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Old 08-07-2013
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Re: "Stupid human trick"--estimate bearings without yr compass

Thanks! Can't wait to look smart.
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Old 08-07-2013
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Re: "Stupid human trick"--estimate bearings without yr compass

I used to lie on my back and look straight between my right and left big-toes and see Johnny Carson.
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Old 08-07-2013
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Re: "Stupid human trick"--estimate bearings without yr compass

Best direction finder; Tell her there's a fashion outlet mall at the proposed destination!
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Re: "Stupid human trick"--estimate bearings without yr compass

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Originally Posted by deniseO30 View Post
Best direction finder; Tell her there's a fashion outlet mall at the proposed destination!
My wife is a thoroughly brilliant businesswoman. I mean really talented. But she has a terrible sense of direction and absolutely cannot read a map. However, she has what I have come to call "Mall Radar". She can find (perhaps by sense of smell or some weird disturbance in the magnetic fields of the Earth) just about any retail establishment on the face of the planet. And she can unerringly find a parking space at any mall, even during the holidays. Its uncanny. I intend to try out Denise's suggestion.
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Re: "Stupid human trick"--estimate bearings without yr compass

So if someone comes too close and you shake your fist at them 10 times they will turn around and piss off?


Thanks, thats good to know.


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Re: "Stupid human trick"--estimate bearings without yr compass

Nolatom, you're absolutely right to know how to figure stuff like that out using commonplace items. Its a very useful skill. That's the kind of stuff I used to mention at social gatherings and everybody would roll their eyes and kind of back away. People like us know that Polaris is more than a wave-runner or snowmobile. Nerds of the world unite! Maybe we could nominate a president!
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Re: "Stupid human trick"--estimate bearings without yr compass

Quote:
Originally Posted by nolatom View Post
So, here's a "stupid Human trick"--estimating degrees of angle w/o instruments

Did you ever want to be able to easily determine approximately how many compass degrees something is from something else?

there's a simple way, no equipment needed (even though yes, you do have a compass I hope).

On average, a fist (with thumb on top, not wrapped around the fingers), on an arm fully extended in front of your eyes, describes an arc of ten degrees, from bottom of pinky finger to top of thumb.

So--is boat A two fists off your headstay? that's 20 degrees. Try doing this with nine fists in succession and you'll see you've made a right angle (90 degrees), whether you are moving horizontally for a terrestrial object, or vertically for a celestial one.

And you can be a latitude-navigator without a sextant. Find the North Star (Big Dipper outer two stars of the spoon point you towards Polaris). Either see (twilight) or estimate your horizontal horizon, and go fist-over fists up to Polaris. Four fists? You're at 40 degrees latitude (Massachusetts!). 3 Fists? New Orleans (I know this one, 30 degrees north of the equator). Latitude navigators discovered the world centuries before they figured out how to find longitude.

How long til sunset (Moonset)? Easy. How many fists from sun down to horizon, or vice-versa? 4 and a half fists? that's 45 degrees. The sun (and all sky objects) "move" at 15 degrees an hour (since Earth rotates 360 of them in 24 hours, si?). So you have 3 hours to finish that dive, or that round of golf. Each fist is worth 10 degrees, so that's 40 minutes of movement. So, if you want cut it closer, each finger/knuckle is worth about 2 degrees, or 8 minutes.

And, a fist is almost 11-1/4 degrees, which is a "Point" forus sailors and historians ("Land ho, 3 points off the port bow!!" a point being 360 degrees divided by 32, if you've ever "boxed" the compass). Now you know what they're talking about in "Moby Dick" and such.

So the human trick ain't so stupid, eh? (hey, trust me, I'm an English Major)
Thanks, good human trick. Now we can say "So the human trick ain't so stupid, eh? (I read on the internet)
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Re: "Stupid human trick"--estimate bearings without yr compass

There's also the Buys Ballots Law trick, using the spread between thumb and pinky when your hand is stretched open as the angle between a storm's center and wind direction. Both handy tricks. Then, of course, there's another useful nautical hand signal: arm straight up vertically or sometimes rapidly hooked under the other arm and then thrust upwards, enumerating 1 with the center finger. It is often flashed to power boaters after they wake you.
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Last edited by smurphny; 08-07-2013 at 07:01 PM.
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