The Norwegian Aurora Polaris Expedition 1902-1903 (Book)

By Kristian Birkeland. Publ. by H. Aschehoug & Co.
Section 1 published 1908;
Section 2 publ. 1913. Out of print.
Online in full FULL TEXT

Extract: Section 2 Chapter VI: On Possible Electric Phenomena in Solar Systems and Nebulae

From the Preface

In his Preface, Birkeland writes:

“The knowledge gained, since 1896, in radio-activity has favoured the view to which I gave expression in that year, namely, that magnetic disturbances on the earth, and aurora borealis, are due to corpuscular rays emitted by the sun.

“During the period from 1896 to 1903 I carried out, in all, three expeditions to the polar regions for the purpose of procuring material that might further confirm this opinion. I have moreover, during the last ten years, by the aid of numerous experimental investigations, endeavoured to form a theory that should explain the origin of these phenomena. It is the results of these investigations that are recorded in this work, the first volume of which treats of terrestrial magnetic phenomena- and earth-currents, this section forming the first two thirds of the volume. The second volume will treat of aurora and some results of meteorological observations made at our stations.

“The leading principle that I have followed in this work has been to endeavour always to interpret the results of the worked-up terrestrial-magnetic observations, and the observations of aurora, upon the basis of my above-mentioned theory.

“[..] experimental investigations with a little magnetic terrella in a large discharge-tube, and by mathematical analysis, we have endeavoured to prove that a current of electric corpuscles from the sun would give rise to precipitation upon the earth, the magnetic effect of which agrees well with the magnetic field of force that was found by the observations on the earth.

“[..] The mathematical investigations, which, together with my experiments, are intended to make clear the movement of electric corpuscles from the sun to the earth, have been carried out, with a perseverance and ingenuity worthy of all admiration, by my friend, Professor STORMER, who will publish the complete results of his investigations in a special part of the present work.

From the Preface (Second section)

“The experimental investigations which at first were designed to procure analogies capable of explaining phenomena on the earth, such as aurora and magnetic disturbances, were subsequently extended, as was only natural, with the object of procuring information as to the conditions under which the emission of the assumed hello-cathode rays from the sun might be supposed to take place.

“The magnetic globe was then made the cathode in the vacuum-box, and experiments were carried on under these conditions for many years.

“It was in this way that there gradually appeared experimental analogies to various cosmic phenomena, such as zodiacal light, Saturn’s rings, sun-spots and spiral nebular.

“The consequence was that attempts were made to knit together all these new discoveries and hypotheses into one cosmogonic theory, in which solar systems and the formation of galactic systems are discussed perhaps rather more from electromagnetic points of view than from the theory of gravitation.

“One of the most peculiar features of this cosmogony is that space beyond the heavenly bodies is assumed to be filled with flying atoms and corpuscles of all kinds in such density that the aggregate mass of the heavenly bodies within a limited, very large space would be only a very small fraction of the aggregate mass of the flying atoms there.

“And we imagine that an average equilibrium exists in infinite space, between disintegration of the heavenly bodies on the one hand, and gathering and condensation of flying corpusles on the other.

Contents (Volume 1)

(Note: Volume 2 was never published)

Section 1

Introduction

The first Expedition, 189
The second Aurora Expedition, 1899—1900
THE EXPEDITION OF 1902–1903
The Auroral Station in Kaafjord
The Auroral Station in Dyrafjord, Iceland
The Auroral Station in Spitsbergen
The Auroral Station in Novaja Semlja
The Working-up of the Material

PART I. MAGNETIC STORMS, 1902-1903.

INVESTIGATIONS BY MEANS OF DIURNAL REGISTERINGS FROM 25 OBSERVATORIES.

CHAPTER I. PRELIMINARY REMARKS CONCERNING OUR MAGNETIC RESEARCHES.

Our Aim and our Method of Working 41
On the Calculation of the Perturbing Force 44
On the Separation of Simultaneous Perturbations 47
CALCULATION OF THE SCALE-VALUES FOR THE REGISTERINGS AT THE NORWEGIAN STATIONS.
Determin1a6t.ion of the Scale-Values for the Dcclinometer 48
Determination of the Sensibility of the Variometers for the Horizontal and Vertical Intensity
Determinations of Sensibility for Kaafjord and Bossekop 50
Determinations of Sensibility for Dyrafjord 51
Determinations of Sensibility for Axeloen 53
Determinations of Sensibility for Matotchkin Schar 54
Temperature Coefficients for the Registerings 55
Explanation of the Charts 56
The topics of the Magnetic Registerings, Explanation and General Remarks 58

CHAPTER II. ELEMENTARY PERTURBATIONS.

General Remarks 61
The Equatorial Perturbations 62
The Positive Equatorial Perturbation . The Perturbation of the 26th January 1903 .
The Perturbations of the 9th December, 1902 70
The Perturbation of the 23rd October, 1902 76
Concerning the Cause of the Positive Equatorial Perturbation 78
The Negative Equatorial Storms 83
The Polar Elementary Storms • •
The Typical Field for the Polar Elementary Storms 85
The Perturbation of the 15th December, 1902 87
Concerning the Cause of the Perturbation 95
The Perturbation of the l0th February, 1903 io6
Concerning the Cause of the Perturbation 113
The Perturbations of the 3oth and 31st March, 1903 115
The Perturbations of the 22nd March, 1903 127
The Perturbations of the 26th December, 1902 137
Cyclo-Median Storms
The Perturbation of the 6th October, 1902 145
Concerning the Cause of the Perturbation 1 49
Further Comparison with Stormer’s Mathematical Theory

CHAPTER III. COMPOUND PERTURBATIONS.

The Perturbation of the 29th and 30th October, 1902 161
The Perturbation of the 25th December, 1902 164
The Perturbation of the 28th December, 1902 169
The Perturbations of the 15th February, 1903 172
The Perturbations of the 7th and 8th February, 1902 187
The Perturbations of the 27th and 28th October, 1902 209
The Perturbations of the 28th and 29th October, 1902 222
The Perturbations of the 31st October and 1st November, 1902 230
How these Perturbations may be explained 234
The Perturbations of the 11th and 12th October, 1902 251
Concerning the Cause of the Perturbations . Positive and negative Polar Storms
The Perturbations of the 23rd and 24th November, 1902 272
The Perturbations of the 26th and 27th January, 1903 286
Further Comparison with the Terrella-Experiments 297

CHAPTER IV. CONCERNING THE INTENSITY OF THE CORPUSCULAR PRECIPITATION IN THE ARCTIC REGIONS OF THE EARTH.

Development of General Formula 303
Numerical Values for Height and Strength of Current 306
The Energy of the Corpuscular Precipitation . The Source of the Sun’s Heat 311

Section 2

PART II. POLAR MAGNETIC PHENOMENA AND TERRELLA EXPERIMENTS.

CHAPTER I. POLAR MAGNETIC STORMS 1882–1883.

The Treatment of the Observations from the Polar Expedition of 1882 & 1883
The Perturbation of the 15th January, 1883 323
The Perturbations of the 2nd January, 1883 339
The Perturbations of the 1st November, 1882 350
The Perturbations of the 14th and 15th February, 1883 361
The Perturbations of the 15th July, 1883 371
The Perturbations of the 1st February, 1883 386
The Perturbations of the 15th December, 1882 397
The Perturbations of the 15th October, 1882 412

CHAPTER II. MATHEMATICAL INVESTIGATIONS. PRELIMINARY RESUME.

The Calculation of the Field of Force for the assumed Polar Current-System 423
Resume 439
A Possible Connection between Magnetic and Meteorologic Phenomena 449

CHAPTER III. STATISTICAL TREATMENT OF MAGNETIC DISTURBANCES OBSERVED AT THE NORWEGIAN STATIONS 1902-1903.

Introductory 451
The Total Storminess as a Function of Time and its Relation to Solar Activity
On the Possible Influence of the Moon upon Magnetic Storms 519
The Seat of the Radiant Source 521
Sun-Spots and Storminess 524
Annual Variation of Storminess 526
On the Diurnal Distribution of Storminess 536
Positive and Negative Storminess 536
P and N Storminess 537
Properties of the <Average Polar Storm> 538
Comparison of Storminess at the four Stations 541
Separation of Great and Small Disturbances 546
The Distribution of Storminess and the Solar Origin of Polar Storms 547
Application to Theory 551

CHAPTER IV. EXPERIMENTS MADE WITH THE TERRELLA WITH THE SPECIAL PURPOSE OF FINDING AN EXPLANATION OF THE ORIGIN OF THE POSITIVE AND NEGATIVE POLAR STORMS.

Introductory 553

STUDY OF RAYS OF GROUP A.

Experiment in which the Terrella had only a Vertical Screen 560
Experiments in which the Terrella is surrounded by a Horizontal Screen 566
Equatorial Rings of Light 569

STUDY OF RAYS OF GROUP B.

The Course of the Rays in the Polar Regions over the Terrella 572
Experiments for determining the Tangential Component of the Polar Precipitation in Relation to the Surface of the Terrella 58o
On an Intimate Connection between Rays of the two Groups A and B 583
On the Size of the Polar Ring of Precipitation 591
The Value of H . ρ for the Helio-Cathode Rays 598
Experiments for the Determination of the Situation of the Polar Zone of Precipitation in Various Positions of the Magnetic Axis 600
Investigations Regarding the Angle formed by the Precipitated Rays with the Magnetic lines of Force. Application to the Polar Aurora 603

CHAPTER V. IS IT POSSIBLE TO EXPLAIN ZODIACAL LIGHT, COMETS’ TAILS, AND SATURN’S RING BY MEANS OF CORPUSCULAR RAYS?

Zodiacal Light 611
Appendix. Expedition to Assouan and Omdurman 624
Magnetic Registerings, the 9th April, 1911 629
Comets’ Tails 631
Halley’s Comet, May, 19 t o 639
Meteorological Observations about the Time of the Transit of Halley’s Comet, 19 to
The Saturnian Ring 654

CHAPTER VI. ON POSSIBLE ELECTRIC PHENOMENA IN SOLAR SYSTEMS AND NEBULAE.

The Sun 661
Experiments showing Analogies to Solar Phenomena 662
Application of the Analogies to further Study of Celestial Phenomena 67o
The Worlds in the Universe 677
Investigations of the Motion of Electric Corpuscles in the Field of an Elementary Magnet especially to find the Conditions fi>r the Approach to Boundary-Circles 678
Study of the Approach to Boundary-Circles, when there is a Resistance in the Medium 686
Study of the Approach to Boundary-Circles, when the Charge of the Particles is variable 693
Study of the Approach to Boundary-Circles outside the Magnetic Equatorial Plane . . . 697
Comparison of Boundary-Circles approached by Different Sorts of Corpuscles
Experiments made with the largest Vacuum-box with a Capacity of loon Litres
On the Charge of Metallic Particles ejected from a Cathode 716
On the Possible Density of flying Corpuscles in Space 720

PART III. EARTH CURRENTS AND EARTH MAGNETISM.

CHAPTER I. EARTH CURRENTS AND THEIR RELATION TO CERTAIN TERRESTRIAL MAGNETIC PHENOMENA .

Introduction 725
Strength and Distribution of Earth-Currents 728
Diurnal Variation of Earth-Currents 729
Earth-Currents and Magnetic Disturbances 730
Earth-Current Registerings at Kaafjord and Bossekop, 1902—1903 73 1
Constants for the Experimental Arrangements 734
The Magnetic Effect of Earth-Currents 736
On the Connection between Polar Storms and Earth-Currents 741
Earth-Currents and Positive Equatorial Perturbations 746
On the Simultaneity of Earth-Currents and Magnetic Disturbances 746
Earth-Currents at Bossekop 748
The Influence of the Earth-Current upon the Vertical Intensity 749
Observations of Earth-Currents at Kaafjord, May, 1910 751
Theoretical Investigation of the Currents that are Induced in a Sphere by Variation of External Current-Systems 757
Numerical Calculation of the Currents 768
Currents that are Induced by Rotation or Removal of the Systems 779
Earth-currents in Lower Latitudes 784
Earth-currents in Germany 784
Earth-currents in France ‘ 788
Earth-currents in England 791
Earth-currents at Pawlowsk 792
Comparison of Simultaneous Earth-Current Observations 793
Consideration of the Conditions during Positive Equatorial Storms 794
The Diurnal Variation of the Earth-Currents 796