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 Triangle”
and 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,
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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