Sunday, July 24, 2022

Could You Survive...The Moon, The Stars and The Navigators Triangle?©

 

 


For more information on the Navigators Triangle, read “The 'Navigator’s Triangle'...What?©”, HERE and for more on how to use the night sky to navigate, look for the future article “How To Find Your Way Without A Compass, Part Four At Night©” – Author’s note

 

A compass rose from A Rational Geography, Part III, by Ernest Young, 1911


So”, I wonder, “what would you do if you suddenly had to find your direction north and you didn’t have a compass?  What if it’s at night, and you can’t use the movement of the Sun or the Shadow-Tip Method1.  Now, what would you do”? 

 

Well, that is the question that the United States Air Force survival expert asked, in his “Could You Survive” article, published in the Spokane Daily Chronicle, on August 30th, 1977.

 


By the light of the Moon

 

Waxing Crescent Moon”, by NASA Visualization Studio.


The Air Force survival expert’s first option was A) to use the Moon to find your cardinal directions, north, south, east, and west, and then from that, to draw a compass rose. 

 

The Moon by itself cannot help you find your directions, but it can help you find a north-south line, if it is in a crescent phase, i.e., the first and last quarters, which it is about half the time.  You can trace an imaginary straight line between the points of a crescent Moon, the horns of the shadowed part, towards the horizon to get an approximate north-south line. 

 

An excerpt from “Star Lore 4”, by Woodland Ways Bushcraft Blog, HERE showing how to use the Moon to find a north -south line in the northern hemisphere.


In the northern hemisphere, the horns of the crescent moon point towards the south, in the southern hemisphere, the points of the crescent show the direction towards north.  Once you know the direction to south in the northern hemisphere, or north in the southern hemisphere, you can fill in the rest of the compass rose from there.

 

This method works because both the Sun and the Moon always move from east to west, and so the imaginary line that you mentally draw between the points of the crescent to the horizon, will be at a right angle to the direction of the Sun, and will show a north-south line.

 

But there are two problems with this method, first about half the time this method won’t work, because it doesn’t work with a full, a half or a new Moon.  And second, when the horns of a crescent Moon are at a sharp angle to the horizon, it can be hard to accurately draw an imaginary straight line to the horizon – a walking stick or any other straight object can help with this, though.

 

The North Star

 

Finding the North Star, from The Stars and Their Stories, 1913, by Alice Mary Matlock Griffith, page 12


The Air Force survival expert’s second pick was B) find Polaris, the North Star, and orient your map with it.

 

The North Star is the best way in the northern hemisphere to find true celestial north, as it is found within about 0.7o of the Earth’s rotational axis2, which is also called the North Celestial Pole.  As the Earth spins on its axis, all the other stars seem to spin in a circle through the night sky, but the North Star appears to stand still, and in the northern hemisphere no matter what season or what time of night it is, following the North Star will lead you due north.

 

The North Star, or Polaris, isn’t the brightest star in the night sky, in fact it is only about the 50th brightest star3 in the night sky.  The easiest way to find the North Star is to first find the “Little Dipper”, also known as the constellation Ursa Minor, or the Little Bear.  The North Star is the last star in the handle of the Little Dipper.

 

Since some of the stars that make up the Little Dipper are easily hidden by just a little moonlight or a few streetlights, the best way to find the North Star is to use the two “Pointer Stars” of the “Big Dipper”, or as it is also known Ursa Major, or the Big Bear.  These two stars in the Big Dipper, Dubhe and Merak, form the side of the dipper farthest away from the handle.  If you draw an imaginary line between these two stars and extend it for about 5 times the distance between them, which is 5o or approximately the width of three fingers when fulling extending your arm, you will find the North Star. 

 

The North Star can also be found, by first finding the constellation of Cassiopeia.

 


Excerpts from Better Ways Of Pathfinding, Robert S. Owendoff, page 82 and 83.

 

The Pointer Stars of the Big Dipper

 


Excerpts from The Stars and Their Stories, 1913, by Alice Mary Matlock Griffith, page 11 and 13

 

The survival expert’s third option was C) to use the Pointer Stars of the Big Dipper to find your directions.

 

Now, as was already mentioned, the two stars in the Big Dipper that form the side farthest away from the handle, are the Pointer Stars, Dubhe and Merak.  While, these two stars can help you find the North Star, by themselves, they cannot help you find a north-south line,

 

From Scales and direction, surveying, projections: A Rational Geography, Part III, by Ernest Young, page 4.

 

The Navigator’s Triangle

 

The Navigators Triangle”, the “Northern Cross” and the line through Deneb to the North Star, the colored lines have been added by the Author, the original, from Wikimedia, HERE.


The last option was D) to locate the Navigator’s Triangleand to plot true north from the brightest star in the triangle.

 

While Vega is the brightest star in the “Navigator’s Triangle”, and one of the brightest stars in the night sky, it cannot help you find the celestial north pole.  However, by finding the “Navigators Triangle”, you can find the “Northern Cross”, which can help you locate the North Star.

 

During the summer, when the “Navigator’s Triangle”3 is visible all night, at nightfall, look towards the east away from the direction of the setting Sun, and find Altair, which is to your right as you face east.  Then, to the left and up from Altair, by about 50o, or about a two hand-spans, which is twice the distance from the tip of your little finger to the tip of your thumb when your arm is fully extended, you will find Vega.  Once you have found Vega, look to your left and down by about a hand-span, or 25o, and you will find Deneb.  To complete the “Navigators Triangle”, look to your right by about two hand-spans, to return to Altair.

 

The “Northern Cross” connects Deneb, which is the tail of Cygnus the Swan, to Sadr and then to the star Albiero to make the vertical pole of a cross.  Then mentally draw a line from Gienah, on the left, through the star Sadr, and on to Rukh on the right, to complete the horizontal pole of the cross.

 

Once, you have found the “Northern Cross”, trace an imaginary line through the sky from Gienah, on the left of horizontal pole of the “Northern Cross”, through Deneb, which is located at the top of the “Northern Cross”, for about one hand-span, plus one fist or palm, or a about 35o, to find the North Star.

 

An excerpt from Earth and Sky Every Child Should Know, by J. E. Rogers, 1910, page 248, showing the “Navigators Triangle”, the “Northern Cross” and the line through Deneb to the North Star, the Author has added the colored lines5.


What did the Survival Experts choose?

 

So”, I ask, “what did you choose?  And did you choose the answer that the United States Air Force survival expert chose”?

 


The survival expert chose, B) find Polaris, the North Star, and orient your map with it.  Did you choose B)”, I wonder, “If so, you picked the right answer, if not, now you know the right answer”!

 

An excerpt from The Stars and Their Stories, 1913, by Alice Mary Matlock Griffith, page 258, the Author has added the colored lines


Don’t forget to come back next week and read “A Hudson Bay Start, A Pro-Tip! ©”, where we will talk about how to get a good start on your next wilderness adventure.

 


I hope that you continue to enjoy The Woodsman’s Journal Online and look for me on YouTube at BandanaMan Productions for other related videos, HERE.  Don’t forget to follow me on both The Woodsman’s Journal Online, HERE, and subscribe to BandanaMan Productions on YouTube.  If you have questions, as always, feel free to leave a comment on either site.  I announce new articles on Facebook at Eric Reynolds, on Instagram at bandanamanaproductions, and on VK at Eric Reynolds, so watch for me.

 

That is all for now, and as always, until next time, Happy Trails!

 

 

Notes

 

1 Although, according to Robert S. Owendoff, the author of Better Ways Of Pathfinding, if the Moon is bright enough to cast a distinct shadow you can use the shadow tip method to create an approximate east-west line from the light of the moon.  You can also use the movement of the stars or the Moon to find an approximate east-west line. 

 

2 From “Polaris: How to find the North Star”, by Vicky Stein, January 24, 2022.

 

3 Ibid.

 

4 For more on the “Navigator’s Triangle” read “The ‘Navigator’s Triangle’...What?©”, HERE.

 

5 Star maps can look confusing as they are not drawn in the normal manner, with west on the left side and with east on the right side of the map.  They are drawn so that they show the sky as it would appear if you were lying down, looking upwards, with your legs pointing south.  In that position as you looked at the night sky, east would be to your left and west on your right.

 

 

Sources

 

Matlock Griffith, Alice Mary; The Stars and Their Stories, [Henry Holt and Company, New York, 1913], pages 11 to 13, 41 to 42 and 258,

https://books.googleusercontent.com/books/content?req=AKW5QafNsnznDDr_ccnzzDmvLfOpEy0dyRJFFSw-vrvTdCcVJ-fourudq0Axrjg67fhYBEKkE-MwWXlROFtAr0hQKuImAVgqk2RboeJjiigLNW-ghhXU1u7ghhEl5OsDI8hnKKtM6x_sr74qSfzMAaDr6Zp7HAU67y-R-Ur0vtZUw9E77fJQb8SzbkpMHHzN1VfYAdnZqg4gyDYfcrloJSRUiv2p7xhvZDwrp7lkkLuEqI55ggMCvKPbPM-UIohHm9UE1WM5Qz7yGc_BT2lh48se7WdGhi3oVA, accessed July 11, 2022

 

Owendoff, Robert S.; Better Ways Of Pathfinding, [The Stackpole Company, Harrisburg, Pennsylvania, 1964], page 82 to 85

 

Rogers, Julia Ellen; Earth and Sky Every Child Should Know, [Doubleday, Page & Company, Garden City, New York, 1910], page 221, https://books.google.com/books?id=0TsIAAAAIAAJ&pg=PA240&dq=stars+of+the+northern+cross&hl=en&newbks=1&newbks_redir=0&sa=X&ved=2ahUKEwi-99rj4_34AhVZD1kFHTuTDNE4FBDoAXoECAQQAg#v=onepage&q=stars%20of%20the%20northern%20cross&f=false, accessed July 16, 2022

 

Spokane Daily Chronicle, “Could You Survive?”, Aug 30, 1977, page 8, https://books.google.com/books?id=fPpLAAAAIBAJ&pg=PA8&dq=%22spokane+daily+chronicle%22+%22could+you+survive%22&article_id=5769,3677539&hl=en&sa=X&ved=2ahUKEwi4l8qYkdv4AhUlMVkFHZQbB8MQ6AF6BAgDEAI#v=onepage&q=%22spokane%20daily%20chronicle%22%20%22could%20you%20survive%22&f=false, accessed July 6, 2022

 

Stein, Vicky; “Polaris: How to find the North Star”, January 24, 2022, [© Future US, Inc.], https://www.space.com/15567-north-star-polaris.html, accessed July 22, 2022

 

Woodland Ways Bushcraft Blog, “Star Lore 4”, [@ 2020 Woodland Ways Ltd.], https://www.woodland-ways.co.uk/blog/natural-navigation-tips/star-lore-4/, accessed July 7, 2022

 

Wikimedia, " Wide-field_view_of_the_Summer_Triangle modifié", by NASA, ESA; https://commons.wikimedia.org/wiki/File:Wide-field_view_of_the_Summer_Triangle_modifi%C3%A9.jpg, accessed July 7, 2022

 

Young, Ernest; Scales and direction, surveying, projections: A Rational Geography, Part III, [George Philip & Son, London, 1911], page 4, https://www.google.com/books/edition/Scales_and_direction_surveying_projectio/JJtIAQAAMAAJ?hl=en&gbpv=1&dq=draw+a+line+from+the+points+of+the+moon+to+find+south&pg=PA4&printsec=frontcover, accessed July 19, 2022

 

 

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