Worlds Without End

WORLDS WITHOUT END BY H. SPENCER JONES M. A., Sc. D., F. R. S. ASTRONOMER ROYAL HONORARY FELLOW, JESUS COLLEGE, CAMBRIDGE Were a star quenched on high, For ages would its light, Still travelling downwards from the sky, Shine on our mortal sight. LONGFELLOW. ii THE ENGLISH UNIVERSITIES PRESS LTD --trui LONDON TO MY FATHER CONTENTS PAGE PREFACE ...... xiii CHAPTER I. THE EARTH OUR HOME ... I II. OUR NEAREST NEIGHBOUR THE MOON . 21 III. THE SUNS FAMILY OF PLANETS . . 36 IV. LIFE IN OTHER WORLDS . . .82 V. COMETS AND SHOOTING STARS . . Q7 VI. THE NEAREST STAR THE SUN . . 113 r VII. GIANT AND DWARF STARS . . . 130 VIII. THE STARS OUR BLOOD RELATIONS . 15 IX. TWIN STARS, PULSATING STARS AND NEW STARS . . . . . .164 X. OUR STELLAR UNIVERSE . . . 1 82 XI. CELESTIAL CATHERINE-WHEELS . . 2OI XII. THE AGE AND EVOLUTION OF THE STARS 215 XIII. WHAT WAS WHAT IS TO BE . . 239 INDEX 257 vii LIST OF ILLUSTRATIONS PLATE I. THE ROYAL OBSERVATORY, GREENWICH Frontispiece FACING PAGE II. THE MOON, AGED l6J DAYS . . . 22 III. PORTION OF MOON, INCLUDING THE SEA OF SERENITY . . . . .26 IV. PORTION OF SOUTHERN HALF OF THE MOON 27 V. THE RANGE OF LUNAR MOUNTAINS THE APENNINES ..... 30 VI. THE RING CRATER, COPERNICUS . - 31 VII. d PHOTOGRAPHS OF MARS AND TERRESTRIAL LANDSCAPE, WITH ULTRA-VIOLET AND INFRA-RED LIGHT . . . - 52 b DRAWING OF MARS, BY LOWELL . 52 VIII. PHOTOGRAPHS OF MARS IN LIGHT OF DIFFERENT COLOURS .... 53 IX. a PHOTOGRAPHS OF JUPITER IN ULTRA VIOLET AND INFRA-RED LIGHT . . 66 b DIFFERENT ASPECTS OF JUPITER . 66 X. a SATURN WITH ITS SYSTEM OF RINGS . 67 b DIFFERENT ASPECTS OF THE RINGS OF SATURN ...... 67 XI. a THREE MINOR PLANET TRAILS . . 78 b PHOTOGRAPHS OF PLUTO ... 78 xii. a HALLEYS COMET IN1910 . . . 102 b BROOKSS COMET igil . . . IO2 xm. a MOREHOUSES COMET 1908 . - 103 b BROOKSS COMET 1903 . . - 103 XIV. d LARGE SUN-SPOT, JULY 31, 1906 . 114 b LARGE SUN-SPOT, JANUARY 2O, 1926 . 114 ix X LIST OF ILLUSTRATIONS PLATE FACING PACK XV. MOTION OF GROUP OF SPOTS ACROSS THE SUN 1 15 XVI. SUCCESSIVE STAGES IN THE DISSIPATION OF A SOLAR PROMINENCE . . Il8 XVII. THE SUN PHOTOGRAPHED IN THE LIGHT OF CALCIUM AND OF HYDROGEN . Iig XVIII. MOTION OF A PROMINENCE FROM THE LIMB OF THE SUN ON TO THE DISC . . 122 XIX. PHOTOGRAPHS OF SUN AT SUN-SPOT MINIMUM AND AT SUN-SPOT MAXIMUM. . - 123 XX. a SOLAR CORONA, MAY Q, IQ2Q . .126 b SOLAR CORONA, MAY 28, igOO . .126 XXI. THE CONSTELLATION OF CARINA, PHOTO GRAPHED WITH EXPOSURES OF I HOUR AND 24 HOURS . . . . - 133 XXII. a PHOTOGRAPHS OF KRUGER 60, SHOWING ORBITAL MOTION . . . - 158 b SPECTRUM OF SUNLIGHT AT TOTAL EC LIPSE, AUGUST 31, 1932 . . . 158 c PORTION OF SPECTRA OF SUN AND OF ALPHA CENTAURI . . . - 158 d SPECTRUM OF ZETA URS MAJORIS AT TWO DIFFERENT DATES . . 158 XXIII. THE MILKY WAY IN THE CONSTELLATION OF AQUILA . . . . . - 177 XXIV. THE MILKY WAY IN THE CONSTELLATION OF SAGITTARIUS . . . . 1 82 XXV. THE MILKY WAY IN THE CONSTELLATIONS OF SCORPIO AND OPHIUCHUS . . .183 XXVI. a THE GREAT NEBULA IN ORION . . 1 88 b DIFFUSE NEBULA IN CYGNUS . . 1 88 XXVII. a ABSORBING CLOUD IN OPHIUCHUS. . 1 89 b ABSORBING CLOUD IN AQUILA . .189 LIST OF ILLUSTRATIONS XI PLATS FACING PACK XXVIII. NEBULOUS REGION IN OPHIUGHUS . IQ2 XXIX. d THE GLOBULAR CLUSTER, OMEGA CEN TAURI . . . . . 193 b SPIRAL NEBULA IN BERENICES HAIR . 193 XXX. DRAWINGS AND PHOTOGRAPH OF THE WHIRLPOOL SPIRAL NEBULA . . 202 XXXI. a THE GREAT SPIRAL NEBULA IN ANDRO MEDA ...... 203 bENLARGEMENT OF SOUTHERN PORTION OF ANDROMEDA NEBULA . . . 203 XXXH. a THE SPIRAL NEBULA, MESSIER 8 1, IN THE GREAT BEAR ..... 242 i THE SPIRAL NEBULA, MESSIER 10 1, IN THE GREAT BEAR .... 242 LIST OF ILLUSTRATIONS xi PLATE FACING PAGE XXVIII. NEBULOUS REGION IN OPHIUCHUS . . IQ2 XXIX. a THE GLOBULAR CLUSTER, OMEGA CEN TAURI . J 93 b SPIRAL NEBULA IN BERENICES HAIR . 193 XXX. DRAWINGS AND PHOTOGRAPH OF THE WHIRLPOOL SPIRAL NEBULA . . 2O2 XXXI. a THE GREAT SPIRAL NEBULA IN ANDRO MEDA - 203 b ENLARGEMENT OF SOUTHERN PORTION OF ANDROMEDA NEBULA . . . 2O3 XXXH...