Part 3

III. The Twenty Brightest Stars in the Heavens 263

IV. A List of the Principal Constellations 264-265

V. Pronunciations and Meanings of Names of Stars and Constellations 266-267

PREFACE

Astronomy, it has been said, is the oldest and the noblest of the sciences. Yet it is one of the few sciences for which most present-day educators seem to find little, if any, room in their curriculum of study for the young, in spite of its high cultural value. It is, we are told, too abstruse a subject for the youthful student. This is doubtless true of theoretical or mathematical astronomy and the practical astronomy of the navigator, surveyor and engineer, but it is not true of general, descriptive astronomy. There are many different aspects of this many-sided science, and some of the simplest and grandest truths of astronomy can be grasped by the intelligent child of twelve or fourteen years of age.

Merely as a branch of nature study the child should have some knowledge of the sun, moon, stars and planets, their motions and their physical features, for they are as truly a part of nature as are the birds, trees and flowers, and the man, woman or child who goes forth beneath the star-lit heavens at night absolutely blind to the wonders and beauties of the universe of which he is a part, loses as much as the one who walks through field or forest with no thought of the beauties of nature that surround him.

The astronomer is the pioneer and explorer of today in realms unknown just as the pioneers and explorers of several centuries ago were to some extent astronomers as they sailed unknown seas and traversed unexplored regions. As the years pass by the astronomer extends more and more his explorations of the universe and brings back among the fruits of discovery measures of giant suns and estimates of the form and extent of the universe, views of whirling, seething nebulæ, mysterious dark clouds drifting through space, tremendous solar upheavals or glimpses of strangely marked surfaces of nearby planets.

In the following pages the author has endeavored to tell in words not beyond the comprehension of the average fourteen-year-old child something of the nature of the heavenly bodies. In Part I an effort is made to make the child familiar with the stars by indicating when and where they can be found in the early evening hours. In addition to identifying the principal constellations and their brightest stars by means of diagrams an attempt has been made to acquaint the child with the most interesting recent discoveries that have been made concerning the principal stars or objects in each group as well as with some of the stories and legends that have been associated with these groups of stars for centuries, and that have been handed down in the folk-lore of all nations.

Chapters 2-13, inclusive, appeared originally with diagrams similar to those shown here, under the department of Nature and Science for Young Folk in St. Nicholas from May, 1921, to April, 1922, inclusive. The Introductory Chapter and Chapters 14 and 15, on the Milky Way and Stars of the Southern Hemisphere, respectively, are published here for the first time, as is also the chapter in Part II on the Evolution of the Stars from Red Giants to Red Dwarfs, which gives the order of the evolution of the stars as now accepted as a result of the brilliant astronomical researches of Dr. Henry Norris Russell of the United States and Prof. A. S. Eddington, of England.

The remaining chapters in Part II have been chosen from a series of articles that have appeared in Science and Invention, formerly The Electrical Experimenter, in the past four years, and have been considerably revised and in some parts rewritten to adapt them to the understanding of more youthful readers. These chapters deal with a variety of astronomical subjects of general popular interest and an effort has been made to select subjects that would cover as wide an astronomical field as possible in a limited space.

The author's aim has not been to write a text-book of astronomy or to treat in detail of any one aspect of this extensive science, but simply to give the average child some general knowledge of the nature of the heavenly bodies, both those that form a part of our own solar system and those that lie in the depths of space beyond.

It has been necessary to write very briefly, and we feel inadequately, of many topics of special interest such as the sun and moon. Books have been written on these two subjects alone as well as upon such subjects as Mars, eclipses, comets, meteors, etc., but the object has been to acquaint the child with the outstanding features of a variety of celestial objects rather than to treat of a few in detail.

If the writer succeeds in arousing the child's interest in the stars so that he may look forth with intelligence at the heavens and greet the stars as friends and at the same time grasps some of the simplest and most fundamental of astronomical truths such as the distinction between stars and planets, the motions of the heavenly bodies and their relative distances from us and the place of our own planet-world in the universe, this book will have served its purpose.

ASTRONOMY FOR YOUNG FOLKS

"The heavens declare the glory of God, and the firmament showeth His handiwork."

Psalm XIX.

THE CONSTELLATIONS

"Canst thou bind the sweet influences of the Pleiades Or loose the bands of Orion? Canst thou bring forth Mazzaroth in his season Or canst thou guide Arcturus with his sons?"

--BOOK OF JOB.

Who would not like to know the stars and constellations by their names and in their seasons as we know the birds and the trees and the flowers, to recognize at their return, year by year, Sirius and Spica, Arcturus and Antares, Vega and Altair, to know when Ursa Major swings high overhead and Orion sinks to rest beneath the western horizon, when Leo comes into view in the east or the Northern Crown lies overhead?

Often we deprive ourselves of the pleasure of making friends with the stars and shut our eyes to the glories of the heavens above because we do not realize how simple a matter it is to become acquainted with the various groups of stars as they cross our meridian, one by one, day after day and month after month in the same orderly sequence. When the robin returns once more to nest in the same orchard in the spring time, Leo and Virgo may be seen rising above the eastern horizon in the early evening hours. When the first snow flies in the late fall and the birds have all gone southward the belt of Orion appears in the east and Cygnus dips low in the west. When we once come to know brilliant blue-white Vega, ruddy Arcturus, golden Capella and sparkling Sirius we watch for them to return each in its proper season and greet them as old friends.

In the following pages we give for each month the constellations or star-groups that are nearest to our meridian, that is, that lie either due north or due south or exactly overhead in the early part of the month and the early part of the evening.

We do not need to start our study of the constellations in January. We may start at any month in the year and we will find the constellations given for that month on or near the meridian at the time indicated.

In using the charts or diagrams of the constellations, we should hold them in an inverted position with the top of the page toward the north or else remember that the left-hand side of the page is toward the east and the right-hand side of the page toward the west, which is the opposite of the arrangement for charts and maps of the earth's surface.

We should also bear in mind that the constellations are all continually shifting westward for the stars and the moon and the planets as well as the sun rise daily in the east and set in the west. This is due to the fact that the earth is turning in the opposite direction on its axis, that is from west to east. In twenty-four hours the earth turns completely around with respect to the heavens or through an angle of 360°, so in one hour it turns through an angle of 360° ÷ 24 or 15°. As a result the stars appear to shift westward 15° every hour. This is a distance about equal in length to the handle of the Big Dipper, which I am sure we all know, even if we do not know another constellation in the heavens.

If, then, we look at the heavens at a later hour than that for which the constellations are given we will find them farther westward and if our time of observation is earlier in the evening than the hour mentioned we will find them farther eastward.

In the course of a year the earth makes one trip around the sun and faces in turn all parts of the heavens. That is, it turns through an angle of 360° with respect to the heavens in a year or through an angle of 360° ÷ 12 or 30° in one month. So as a result of our revolution around the sun, which is also in a west to east direction, we see that all the constellations are gradually shifting westward at the rate of 30° a month. It is for this reason that we see different constellations in different months, and it is because of the turning of the earth on its axis that we see different constellations at different hours of the night.

If we should sit up from sunset to sunrise and watch the stars rise in the east, pass the meridian and set in the west--as the sun does by day--we should see in turn the same constellations that are to pass across the heavens in the next six months. This is because in twelve hours' time we are carried through the same angle with respect to the heavens by the earth's rotation on its axis that we are in the next six months by the motion of the earth around the sun.