Beyond the Edge: Historic Stories of Polar Navigation: Beyond the Edge, #3

By Gerald Johnson

Before GPS, celestial navigation was an essential part of polar exploration. It was so critical that it was often the cause of the success or failure of expeditions. Beyond the Edge, Vol. III relates firsthand accounts of the critical role played by navigators in arctic exploration.

• Language: English
• Publisher: Traction Books
• Release date: Oct 31, 2023
• ISBN: 9781735085784

Book preview

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Copyright © 2020 Gerald W. Johnson

All rights reserved. No part of this book may be reproduced in any form or by any electronic or mechanical means, including information storage and retrieval systems, without permission in writing from the publisher, except by reviewers, who may quote brief passages in a review.

ISBN 978-1-7350857-8-4

"It was hard upon high noon; and Ahab, seated in the bows of his high-hoisted boat, was about taking his wonted daily observation of the sun to determine his latitude.

...he again looked up towards the Sun and murmured to himself: thou sea-mark! thou high and mighty Pilot! thou tellest me truly where I am—but canst thou cast the least hint where I shall be?"

—Herman Melville

Moby-Dick

When the mariner has been tossed for many days in thick weather, and on an unknown sea, he naturally avails himself of the first pause in the storm, the earliest glance of the sun, to take his latitude, and ascertain how far the elements have driven him from his true course.

—Daniel Webster

January 26, 1830

For all the polar navigators who, like Ahab, have looked to the sun to determine their latitude.

CONTENTS

Preface: Polar Navigation and Mapping

Introduction: Celestial Navigation

Part One: Historic Expeditions

Chapter 1: Greenland

Chapter 2: The North Pole

Chapter 3: The South Pole

Chapter 4: The Antarctic Voyage of the James Caird

Part Two: A New Era of Polar Exploration

Chapter 5: Blue Trek

Chapter 6: Project Nord

Chapter 7: LOREX

Epilogue

Acknowledgements

Sources

About the Author

PREFACE

POLAR NAVIGATION AND MAPPING

THE GOLDEN ERA OF POLAR exploration and mapping occurred during the late nineteenth century and well into the twentieth century. Explorers traversed the featureless ice and snow, sailed the treacherous polar seas, and mapped unknown lands. Their exploits are well documented by both the participants themselves and later by historians.

Not as well recorded, however, is how early explorers found their way in these vast uncharted regions. The ability to successfully navigate often determined whether an expedition would accomplish its goals and, more importantly, whether its members would live or die.

Later expeditions began to fill in the blank areas of these uncharted regions. As the requirements of polar exploration changed, navigational techniques evolved from those that had sufficed for hundreds of years to modern satellite-based systems.

Beyond the Edge, Vol. III is a small compendium of the navigation involved in these endeavors, both old and new.

INTRODUCTION

CELESTIAL NAVIGATION

THE UNIVERSAL MEANS OF DEFINING the location of a point on the earth’s surface is to denote its latitude and longitude. There are several ways of arriving at these values, from approximated estimates to sophisticated and complicated techniques. Historically, polar exploration and mapping, because of its remoteness, relied on celestial navigation. This is the science of using the known celestial position of the sun, moon, planets, or stars to determine the unknown position of points on the surface of the earth. To a large extent celestial navigation has now been replaced by satellite navigation, but a fundamental knowledge of the earlier method provides an appreciation of its role in the early days of polar exploration and mapping.

Lines of latitude encircle the earth in an east/west direction and are denoted by their angular distance, north or south (0°–90°) from the equator. Lines of longitude, also known as meridians, encircle the earth in a north/south direction and are denoted by their angular distance, east or west (0°–180°) from the Prime Meridian which passes through Greenwich, England. The North and South Poles are the points where all meridians converge. These lines of latitude and longitude are imaginary, but they are printed on maps and navigational charts as if they existed.

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The sun, moon, planets, and navigational stars are located in the sky by their Greenwich Hour Angle (GHA) or by their Sidereal Hour Angle (SHA), both of which are comparable to longitude; and by their declination, which is comparable to latitude. For the sun, moon and planets, these values are constantly changing as the moon and planets rotate and revolve, but for the stars, which are outside our solar system, these values are essentially fixed. All the values needed for celestial navigation are available in a volume called The Nautical Almanac¹.

In addition to the universal standard for location (latitude and longitude), a universal standard for time is also required for navigation. Navigators now use Coordinated Universal Time (UTC), earlier called Greenwich Mean Time (GMT), which is set when the sun crosses the Greenwich meridian at noon (12:00 UTC/GMT).

The process of determining a position begins by measuring the vertical angle of a celestial body above a horizontal plane. For this, one of two instruments is used: either a sextant or a transit. The sextant is handheld, whereas the transit (also known as a theodolite) is mounted on a tripod set on the ground. Historically the sextant has been used at sea by a ship’s navigator, and the transit, a more versatile instrument, is used on land by surveyors.