Chapter I: Part 1

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A FIELD BOOK
OF
THE STARS

WILLIAM TYLER OLCOTT

_Second Edition, revised and enlarged_

WITH FIFTY DIAGRAMS

G.P. PUTNAM'S SONS
NEW YORK AND LONDON
The Knickerbocker Press

_Printed in the United States of America_

INTRODUCTION.

Considering the ease with which a knowledge of the constellations can be acquired, it seems a remarkable fact that so few are conversant with these time-honored configurations of the heavens. Aside from a knowledge of "the Dipper" and "the Pleiades," the constellations to the vast majority, are utterly unknown.

To facilitate and popularize if possible this fascinating recreation of star-gazing the author has designed this field-book. It is limited in scope solely to that purpose, and all matter of a technical or theoretical nature has been omitted.

The endeavor has been to include in these pages only such matter as the reader can observe with the naked eye, or an opera-glass. Simplicity and brevity have been aimed at, the main idea being that whatever is bulky or verbose is a hindrance rather than a help when actually engaged in the observation of the heavens.

The constellations embraced in this manual are only those visible from the average latitude of the New England and Middle States, and owe their place in the particular season in which they are found to the fact that in that season they are favorably situated for observation.

With this brief explanatory note of the purpose and design of the book, the author proceeds to outline the scheme of study.

SCHEME OF STUDY.

The table of contents shows the scheme of study to be pursued, and to facilitate the work it is desirable that the student follow the therein circumscribed order.

A knowledge on the part of the reader of Ursa Major, or "the Dipper" as it is commonly called, and "the Pleiades," the well-known group in Taurus, is presupposed by the author.

With this knowledge as a basis, the student is enabled in any season to take up the study of the constellations. By following out the order dictated, he will in a few nights of observation be enabled to identify the various configurations making up the several constellations that are set apart for study in that particular season.

A large plate, showing the appearance of the heavens at a designated time on the first night of the quarter, is inserted before each season's work. This should be consulted by the student before he makes an observation, in order that he may obtain a comprehensive idea of the relative position of the constellations, and also know in what part of the heavens to locate the constellation which he wishes to identify.

A knowledge of one constellation enables the student to determine the position of the next in order. In this work, the identification of each constellation depends on a knowledge of what precedes, always bearing in mind the fact that each season starts as a new and distinct part to be taken by itself, and has no bearing on that which comes before.

CONTENTS

PAGE

INTRODUCTION iii

SCHEME OF STUDY v

The Constellations of Spring.

MAP OF THE HEAVENS 9 P.M., APRIL FIRST 3

1. URSA MAJOR 4

2. URSA MINOR 6
Located by the pointer stars in Ursa Major.

3. GEMINI 8
Located by a line drawn through designated stars
in Ursa Major.

4. AURIGA 10
Located in the same manner as Gemini.

5. CANCER 12
Located by a line drawn from Auriga to Gemini
and prolonged.

6. HYDRA 14
The head of Hydra is to be seen just below Cancer.

7. LEO 16
Located by a line drawn from Gemini to Cancer
and prolonged.

8. COMA BERENICES 18
Position indicated by drawing a line through
designated stars in Leo.

9. CANIS MINOR 20
Located by a line drawn from Auriga to Gemini
and prolonged.

10. CORVUS 22
Located by a line drawn from Ursa Minor through
Ursa Major and prolonged.

11. CRATER 24
Located south of Leo and just west of Corvus.

METEORIC SHOWERS, APRIL TO JULY 26

The Constellations of Summer.

MAP OF THE HEAVENS 9 P.M., JULY FIRST 31

12. DRACO 32
Lies between Ursa Major and Ursa Minor, coiling
about the latter.

13. LYRA 34
Vega, its brightest star, is 12[deg] S.W. of the Dragon's
head.

14. CYGNUS 36
Deneb, its brightest star, is about 20[deg] east of Vega.

15. AQUILA 38
Located by a line drawn from the Dragon's head
through Vega and prolonged.

16. DELPHINUS 40
Located about 10[deg] northeast of Altair in Aquila.

17. SAGITTARIUS 42
Located by a line drawn from Cygnus to Aquila
and prolonged.

18. OPHIUCHUS AND SERPENS 44
Located by a line drawn from Delphinus to Aquila
and prolonged.

19. SCORPIUS 46
Located just under Ophiuchus, and west of Sagittarius.

20. LIBRA 48
Located about 15[deg] west of the head of Scorpius.

21. CORONA BOREALIS 50
Located just above the head of Serpens.

22. HERCULES 52
Located by lines drawn from either Vega or Altair
to Corona.

23. BO[:O]TES 54
Located just west of the Crown. Arcturus, its
brightest star, is about 30[deg] southeast of [[^e]] Ursae
Majoris.

24. VIRGO 56
Spica, its brightest star, is located by a line drawn
from Antares in Scorpius through [a] in Libra and
prolonged about 20[deg].

25. CANES VENATICI 58
Cor Caroli, its brightest star, is about 17[deg] south
of Alioth in Ursa Major.

METEORIC SHOWERS, JULY TO OCTOBER 60

The Constellations of Autumn.

MAP OF THE HEAVENS 9 P.M., OCTOBER FIRST 65

26. CASSIOPEIA 66
Located by a line drawn from Ursa Major through
the Pole star, the position of which is indicated
by the pointer stars [a] and [b] Ursae Majoris.

27. CEPHEUS 68
Located by pointer stars in Cassiopeia.

28. PEGASUS 70
The great square of Pegasus is located by a line
drawn from Polaris to Cassiopeia and prolonged.

29. ANDROMEDA 72
The star Alpheratz in Andromeda is at the northeast
corner of the great square of Pegasus.

30. PERSEUS 74
Lies 9[deg] east of [g] Andromedae.

31. PISCES 76
The Circlet in Pisces is to be seen just below
Pegasus.

32. TRIANGULUM 78
A line drawn from Pegasus to Perseus passes through
[b] in Triangulum.

33. AQUARIUS 80
The position of the water jar of Aquarius is determined
by pointer stars in Pegasus.

34. CAPRICORNUS 82
The head of the Sea Goat is located by a line drawn
from [a] Pegasi through [z] and [th] Pegasi and prolonged
about 25[deg].

35. ARIES 84
Lies just south of Triangulum. A line drawn
from [g] Andromedae through [b] Trianguli points
out [a] Arietis.

36. CETUS 86
The head of Cetus lies about 20[deg] southeast of
Aries.

37. MUSCA 88
Located between Triangulum and Aries.

METEORIC SHOWERS, OCTOBER TO JANUARY 90

The Constellations of Winter.

MAP OF THE HEAVENS 9 P.M., JANUARY FIRST 95

38. TAURUS 96
Contains the celebrated and unmistakable group,
The Pleiades, to be seen almost overhead in
the early evening during the Winter months.

39. ORION 98
The tips of the horns of the Bull are pointer stars
to Betelgeuze, in Orion.

40. LEPUS 100
Located just below Orion.

41. COLUMBA 102
Located south of Lepus, close to the horizon.

42. CANIS MAJOR 104
Located by a line drawn from the stars forming
Orion's girdle.

43. ARGO NAVIS 106
Located by a line drawn from Orion to Canis
Major and prolonged 18[deg].

44. MONOCEROS 108
Located just east of Orion.

45. ERIDANUS 110
Located just west of Rigel, in Orion.

METEORIC SHOWERS, JANUARY TO APRIL 112

THE PLANETS 115

THE MILKY WAY 124

THE MOTIONS OF THE STARS 126

METEORS, OR SHOOTING STARS 130

NAMES OF THE STARS AND THEIR MEANINGS 133

INDEX 159

THE DIAGRAMS.

The diagrams, it will be observed, are grouped under the seasons, and they indicate the positions of the constellations as they appear at 9 o'clock P.M. in mid-season.

To facilitate finding and observing the constellations, the student should face in the direction indicated in the text. This applies to all constellations excepting those near the zenith.

The four large plates are so arranged that the observer is supposed to be looking at the southern skies. By turning the plate about from left to right, the eastern, northern, and western skies are shown successively.

On many of the diagrams the position of nebulae is indicated. These are designated by the initial letter of the astronomer who catalogued them, preceded by his catalogue number, as for instance 8 M. signifies nebula number 8 in Messier's catalogue.

The magnitudes assigned to the stars in the diagrams are derived from the Harvard Photometry. When a star is midway between two magnitudes the numeral is underlined, thus _2_, indicates a star of magnitude 2.5.

If a star's magnitude is between 1 and 1.5 it is regarded as a first-magnitude star. If it lies between 1.5 and 2 it is designated second magnitude.

THE CONSTELLATIONS OF SPRING.

N. at 9 o'clock April 1st.]

URSA MAJOR (er'sa m[=a]'-jor)--THE GREAT BEAR. (Face North.)

LOCATION.--Ursa Major is probably the best known of the constellations, and in this work I presuppose that the reader is familiar with its position in the heavens. It is one of the most noted and conspicuous constellations in the northern hemisphere, and is readily and unmistakably distinguished from all others by means of a remarkable cluster of seven bright stars in the northern heavens, forming what is familiarly termed "The Dipper."

The stars [a] and [b] are called the pointers, because they always point toward the Pole Star, 28-3/4[deg] distant from [a].

Alioth is very nearly opposite Shedir in Cassiopeia, and at an equal distance from the Pole. The same can be said of Megres, in Ursa Major, and Caph, in Cassiopeia.

The star [o] is at the tip of the Bear's nose. A clearly defined semicircle begins at [o] and ends in the pair [i] and [k] at the extremity of the Bear's right fore paw. This group of stars resembles a sickle. Note little Alcor close to Mizar. This star was used by the Arabs as a test of good eyesight.

Mizar and Alcor are known as the horse and his rider.

This plate shows the Bear lying on his back, his feet projected up the sky; three conspicuous pairs of stars represent three of his four feet.

The Chaldean shepherds and the Iroquois Indians gave to this constellation the same name. The Egyptians called it "The Thigh."

[a] and [[^e]] are moving through space in a contrary direction to the remaining five stars in "The Dipper."

URSA MINOR (er'-sa mi'-nor)--THE LITTLE BEAR. (Face North.)

LOCATION.--The two pointer stars in Ursa Major indicate the position of Polaris, the North Star, which represents the tip of the tail of the Little Bear, and the end of the handle of the "Little Dipper." In all ages of the world, Ursa Minor has been more universally observed and more carefully noticed than any other constellation, on account of the importance of the North Star.

Polaris is a little more than 1-1/4[deg] from the true pole. Its light takes fifty years to reach us.

A line joining [b] Cassiopeiae, and Megres, in Ursa Major, will pass through Polaris.

At the distance of the nearest fixed star our sun would shine as a star no brighter than Polaris which is presumably about the sun's size.

Polaris revolves around the true pole once in twenty-four hours in a little circle 2-1/2[deg] in diameter. Within this circle two hundred stars have been photographed.

The North Star is always elevated as many degrees above the horizon as the observer is north of the equator.

Compare the light of the four stars forming the bowl of the "Little Dipper," as they are each of a different magnitude. A standard first-magnitude star is 2-1/2 times brighter than a standard second magnitude star, etc.

GEMINI (jem'-i-ni)--THE TWINS. (Face West.)

LOCATION.--A line drawn from [b] to [k] Ursae Majoris and prolonged an equal distance ends near Castor, in Gemini. Gemini is characterized by two nearly parallel rows of stars. The northern row if extended would reach Taurus, the southern one Orion. Note the fine cluster 35 M. Herschel discovered Uranus in 1781 a short distance southwest of it. Two wonderful streams of little stars run parallel northwest on each side of the cluster. Where the ecliptic crosses the solstitial colure is the spot where the sun appears to be when it is farthest north of the equator, June 21st. Castor is a fine double for a telescope, and Pollux has three little attendant stars. An isoceles triangle is formed by Castor, Aldebaran in Taurus, and Capella in Auriga. There is a record of an occultation in Gemini noted about the middle of the fourth century B.C.

The Arabs saw in this group of stars two peacocks, the Egyptians two sprouting plants, and the Hindus twin deities, while in the Buddhist zodiac they represented a woman holding a golden cord. Since classic times, however, the figure has always been that of human twins.

At the point indicated near [th] a new star was discovered by Enebo in March, 1912. It attained a maximum of about magnitude 3.5 and has at this writing waned to the eleventh magnitude.

AURIGA ([^a]-ri'-ga)--THE CHARIOTEER. (Face Northwest.)

LOCATION.--A line drawn from [d] to [a] Ursae Majoris, and prolonged about 45[deg], ends near the bright Capella, in Auriga, a star of the first magnitude, and one of the most brilliant in the heavens. It is unmistakable, having no rival in brightness near it. Auriga is a beautiful and conspicuous constellation. It is characterized by a clearly defined pentagon. Note the three fourth-magnitude stars near Capella known as "The Kids." The star [b] is common to Auriga and Taurus, being the former's right foot and the latter's northern horn. The field within the pentagon is particularly rich in clusters. Capella forms a rude square with Polaris, [e] Cassiopeiae, and [o] Ursae Majoris, and forms an equilateral triangle with Betelgeuze in Orion, and the Pleiades in Taurus.

A line from [th] to [a] Aurigae prolonged about 20[deg] ends near [a] Persei.

Capella is visible at some hour of every clear night throughout the year. Of the first-magnitude stars it is nearest to the Pole, and it rises almost exactly in the northeast.

To the Arabs Capella was "The Driver," because it seemed to rise earlier than the other stars and so apparently watched over them, or still more practically as "The Singer" who rode before the procession cheering on the camels, which last were represented by the Pleiades.

CANCER (kan'-ser)--THE CRAB. (Face West.)

LOCATION.--Cancer lies between Gemini and Leo. A line drawn from Nath in Auriga to Pollux in Gemini, and prolonged about 15[deg], ends in Praesepe, the Manger, the great star cluster in Cancer, which is also called "The Bee Hive." It contains 300 stars. The stars [g] and [d] are called the Aselli--the ass's colts feeding from the silver manger.

The star [b] lies about 10[deg] northeast of Procyon. Acubens, [a] lies on the same line the same distance beyond [b]. These two stars form the tips of the inverted "Y" which distinguishes Cancer.

An imaginary line from Capella through Pollux will point out Acubens. Close to it are two faint stars. The Bee Hive lies within an irregular square formed by [g], [d], [[^e]], and [th], and looks like a nebula to the naked eye.

In June, 1895, all the planets except Neptune were in this quarter of the heavens, and Halley's comet was in this constellation on its first appearance in 1531.

The dimness of [g] and [d] is an infallible precursor of rain, and if the Bee Hive is not visible in a clear sky, it is a presage of a violent storm.

HYDRA (hi'-dra)--THE SEA-SERPENT. (Face South and Southwest.)

LOCATION.--The head of Hydra, a striking and beautiful arrangement of stars, lies just below the Bee Hive, in Cancer, 6[deg] south of Acubens in that constellation, and forms a rhomboidal figure of five stars.

Hydra is about 100[deg] in length and reaches almost from Canis Minor to Libra. Its stars are all faint except Alphard, or the Hydra's heart, a second-magnitude star remarkable for its lonely situation, southwest of Regulus, in Leo. A line drawn from [g] Leonis through Regulus points it out. It is of a rich orange tint. Castor and Pollux, in Gemini, point southeast to it.

The constellations Crater, the Cup, and Corvus, the Crow, both stand on the coils of Hydra, south of Denebola, the bright star in the tail of the Lion.

Hydra is supposed to be the snake shown on a uranographic stone from the Euphrates, 1200 B.C.

The little asterism Sextans, the Sextant, lies in the region between Regulus and Alphard. It contains no stars brighter than the fourth magnitude.

LEO (le'o)--THE LION. (Face South.)

LOCATION.--A line drawn from Pollux, in Gemini, to [g] in Cancer, and prolonged about 12[deg], strikes Regulus, the brilliant star in the heart of the Lion. Regulus lies about 9[deg] east of Acubens, in Cancer, and about 12[deg] northeast of Alphard, in the heart of Hydra.

Leo is one of the most beautiful constellations in the zodiac. It lies south of the Great Bear, and its principal stars are arranged in the form of a sickle which nearly outlines the Lion's head. This group is so striking as to be unmistakable. Regulus is in the handle of the sickle. It is one of the stars from which longitude is reckoned, lies almost exactly on the ecliptic, and is visible for eight months in the year.

Denebola, the bright star in the Lion's tail, lies 25[deg] east of Regulus, and about 35[deg] west of Arcturus, in Bo[:o]tes. It is the same distance northwest of Spica, in Virgo, and forms with Spica and Arcturus a large equilateral triangle.

[z] is double, and has three faint companion stars.

[e] has two seventh-magnitude companion stars, forming a beautiful little triangle.

Regulus is white in color, [g] yellow, [p] red.

[g] is a beautiful colored telescopic double star and has a companion visible in an opera-glass.

The figure of Leo very much as we now have it appears in all the Indian and Egyptian zodiacs.

THE SICKLE]

COMA BERENICES (k[=o]'-ma ber-e-ni'-sez)--BERENICE'S HAIR.

LOCATION.--A line drawn from Regulus to Zosma, in Leo, and prolonged an equal distance, strikes this fine cluster, which is 18[deg] northeast of Zosma, [d] Leonis.

The group lies well within a triangle formed by Denebola, Arcturus, in Bo[:o]tes, and Cor Caroli, in Canes Venatici, which triangle is the upper half of the Diamond of Virgo.

Twenty or thirty stars in this group can be counted with an opera-glass, and the group can be easily distinguished with the naked eye, when the moon is not visible.

The first half of the month of April can be called the most brilliant sidereal period of the year. At this time eleven first-magnitude stars are visible in this latitude at 9 P.M. From east to west they are: Vega, Arcturus, Spica, Regulus, Pollux, Procyon, Sirius, Capella, Aldebaran, Betelgeuze, and Rigel, truly a glorious company, an incomparable sight.

CANIS MINOR (k[=a]'-nis mi'-nor)--THE LESSER DOG. (Face West.)

LOCATION.--Procyon, the Little Dog Star, lies about 23[deg] south of Pollux, in Gemini. A line drawn from Nath, in Auriga, to Alhena, in Gemini, and prolonged about 18[deg], reaches Procyon.

Procyon is equidistant from Betelgeuze in Orion, and Sirius in Canis Major, and forms with them an equilateral triangle. It forms a large right-angled triangle with Pollux and Betelgeuze.

The light from Procyon is golden yellow. Four degrees northwest of it is the third-magnitude star Gomeisa. The glass shows two small stars forming a right-angled triangle with it.

Procyon was distinctly mentioned by Ptolemy. It rises in this latitude a little north of east about half an hour before Sirius, the Dog Star, hence it was called Procyon from two Greek words which signify "before the dog."

Procyon is one of our nearest neighbors in space, at a distance of ten light years, and is attended by a very faint companion which is only visible in the largest telescopes.

CORVUS (k[^o]r'-vus)--THE CROW. (Face South.)

LOCATION.--A line drawn from the Bee Hive, in Cancer, through Regulus, in Leo, and prolonged about 40[deg], ends near the conspicuous quadrilateral which distinguishes Corvus. The brightest star in this region of the sky is Spica, in Virgo. It lies about 10[deg] northeast of Algorab.

[z] is a double star for an opera-glass. A faint pair of stars lie close below and to the west of [b]. The Crow is represented as standing on, and pecking at, the coils of Hydra. The star Al Chiba is in the Crow's bill.

Corvus was known as the Raven in Chaucer's time.

[d] is an interesting telescopic double.

A line drawn from [g] to [b] Corvi and prolonged twice its length locates the third-magnitude star [i] Centauri in the right shoulder of the Centaur. The brightest stars in this constellation are not visible in this latitude.

CRATER (kr[=a]'-ter)--THE CUP. (Face South.)

LOCATION.--Crater is situated 15[deg] west of Corvus, and due south of [th] Leonis. It is easily distinguished by reason of a beautiful and very striking semicircle of six stars of the fourth magnitude, forming the bowl of the cup.

The constellation resembles a goblet with its base resting on the coils of Hydra.

The star Alkes is common to Hydra and Crater, and may be seen 24[deg] southeast of Alphard in the heart of Hydra. It is distinguished by its forming an equilateral triangle with [a] and [g], stars of the same magnitude 6[deg] south and east of it.

Corvus and Crater are to be seen half-way up the southern sky during the early evenings in spring.

[d] is now the lucida.

Crater is situated at about the centre of Hydra and is on the meridian, April 26th. Owing to its many faint stars it is best seen on a clear moonless night.

The zodiacal light is well worth observing at this season of the year. It is to be seen in the western sky shortly after sundown, and is most intense during the evenings of March.

METEORIC SHOWERS.

APRIL TO JULY.

+--------------------+---------+--------------------+---------------+-------------+--------+
| | | | | Other Dates | |
| Name of Shower | Date | Radiant Point |Characteristics| of |Location|
| | | | | Observation | |
+--------------------+---------+--------------------+---------------+-------------+--------+
| Beta or Mu |Apr. 9-16| The Dragon's head | | | N.E. |
| Draconids | Apr. 18 | | Sw. F. | Apr. 17-25 | |
| Beta Serpentids | | The Serpent's head | | | S.E. |
+--------------------+---------+--------------------+---------------+-------------+--------+
| Lyrids, | | About 10[deg] from | | | |
| rich shower | Apr. 20 | Vega toward | V. Sw. | | N.E. |
| | | Hercules | | | |
+--------------------+---------+--------------------+---------------+-------------+--------+
| Eta Aquarids, | May 6 | Near the Water | Sw. Sk. | After 2 A.M.| E. |
| fine annual shower | | Jar | | | |
+--------------------+---------+--------------------+---------------+-------------+--------+
| Alpha Coronids, | May 11 | Near Gemma | Sl. F. | May 7-18 | N. |
|well defined in 1885| | ([a]) Coronae B. | | | |
+--------------------+---------+--------------------+---------------+-------------+--------+
| Iota Pegasids, | | Between Cygnus | Sw. Sk. | May 29- | |
|well defined shower | May 30 | and the Great | |June 4 after | N.E. |
| | | Square | | 10 P.M. | |
+--------------------+---------+--------------------+---------------+-------------+--------+
| Beta Herculids | June 7 | Near the Crown | Sl. B. | A fire ball | S.E. |
| | |About 8[deg]S. of | | radiant | |
| Beta Ophiuchids | June 10 | Ras Alhague | Sl. | June 10, 13 | S.E. |
+--------------------+---------+--------------------+---------------+-------------+--------+
| Delta Cepheids | June 20 | About 13[deg] from | | June 10-28, | |
| | | ([b]) Cassiopeiae | Sw. |July 19, Aug.| N. |
| | | | | 25, etc. | |
+--------------------+---------+--------------------+---------------+-------------+--------+

The Abbreviations under _Characteristics_ are as follows:

V.--very. M.--moderately. Sw.--swift. Sl.--slow. Sh.--short. B.--bright. F.--faint. Sk.--streak-leaving meteors. T.--train-leaving meteors.

THE CONSTELLATIONS OF SUMMER.

N. at 9 o'clock, July first.]

DRACO (dr[=a]'-ko)--THE DRAGON. (Face North.)

LOCATION.--About 10[deg] from [a] Ursae Majoris--from [a] to [d] is 10[deg]--slightly south of, that is above, the line from [a] to Polaris, is Giansar, [l] in the tip of the Dragon's tail. Above [l], and almost in line with it, are two more stars in Draco, which form with two stars in Ursa Major a quadrilateral. (See diagram.) Draco now curves sharply eastward, coiling about the Little Bear as shown, then turns abruptly southerly, ending in a characteristic and clearly defined group of four stars, forming an irregular square, representing the Dragon's head. This group is almost overhead in the early evening in summer. The star in the heel of Hercules lies just south of the Dragon's head. The brilliant Vega will be seen about overhead, 12[deg] southwest of the Dragon's head. Eltanin, one of the Dragon's eyes, is noted for its connection with the discovery of the law of aberration of light. It is of an orange hue, while the star [b], near it, is white. Note Thuban, once the Pole Star, at one corner of a quadrilateral that Draco forms with Ursa Major.

Thuban could be seen by day or night from the bottom of the central passage of several of the Pyramids in Egypt.

The rising of Eltanin was visible about thirty-five hundred years B.C. through the central passages of the temples of Hathor at Denderah. The Egyptians called Draco "The Hippopotamus."

Vega and the four stars in the Dragon's head offer an opportunity to compare the first five stellar magnitudes with which all should be familiar.

LYRA (l[=i]'-ra)--THE LYRE.

LOCATION.--Lyra may be easily distinguished because of the brilliant Vega, its brightest star, which is situated about 12[deg] southwest of the Dragon's head. It is unmistakable, as it is the brightest star in this region of the heavens, and the third brightest in this latitude. In July and August Vega is close to the zenith in the early evening.

The six bright stars in Lyra form an equilateral triangle on one corner of a rhomboid. A very characteristic figure.

[e] is a pretty double for an opera-glass, and a 3" glass reveals the duplicity of each star of this pair. [e] is therefore a double double.

[z] is a double for a good glass.

[b] is a variable, changing from magnitude 3.4 to 4.4 in twelve days. At its brightest it is about equal to its near neighbor [g] Lyrae.

The noted ring nebula lies between [b] and [g]. A 3" glass reveals it but a powerful telescope is required to render its details visible.

If the distance from the earth to the sun equalled one inch, the distance from the earth to Vega would be 158 miles.

Vega was the first star to be photographed, in 1850. It is visible at some hour every clear night, and has been called the arc-light of the sky. Its light has the bluish-white hue that suggests "a diamond in the sky."

The spectroscope reveals that Vega is a star probably only in its infancy, as hydrogen is its predominating element.

CYGNUS (sig'-nus)--THE SWAN, OR THE NORTHERN CROSS.

LOCATION.--Deneb, the brightest star in Cygnus, is at the top of the cross, and a little over 20[deg] east of Vega. It forms a triangle with Vega and Altair in Aquila--Altair being at the apex, about 35[deg] from Deneb and Vega.

[b] Cygni is at the base of the cross, and a line drawn from Vega to Altair nearly touches it. It is a beautiful colored double for a small telescope.

Note "61," one of the nearest stars to us. It was the first star whose distance was measured (by Bessel in 1838). It is a double star and 10.4 light years distant.

The cross is nearly perfect and easily traced out. It lies almost wholly in the Milky Way.

Note "The Coal Sack," one of the dark gap in the Milky Way.

Cygnus contains an unusual number of deeply colored stars and variable stars.

[o] Cygni has a sixth-magnitude companion, and [g] is in the midst of a beautiful stream of faint stars.

This region is perhaps richer than any similar extent in the heavens. An opera-glass will reveal many of its beauties.

Herschel counted 331,000 stars in an area of only 5[deg] in Cygnus.

AQUILA (ak'-wi-l[:a])--THE EAGLE, AND ANTINO[:U]S. (Face Southeast.)

LOCATION.--Half-way up the sky in the Milky Way, you will see three stars in a line, the middle one much brighter than the other two. This bright star is Altair, in Aquila. It forms with Vega and Deneb an isosceles triangle. Altair is at the apex, about 35[deg] from the other two. A triangle is formed by Vega, Altair, and Ras Alhague, in the Serpent Bearer, which is about 30[deg] west of Altair.

This is a double constellation composed of Aquila and Antino[:u]s. Altair is in the neck of the Eagle, Alschain in the head of Antino[:u]s.

When the moon is absent, a rude arrowhead can be traced out, embracing almost all the stars in Aquila.

[[^e]] is an interesting variable star, changing from magnitude 3.5 to 4.7 and back again within a period of 7 days 4 hours 12 minutes.

Altair rises about 8[deg] north of the exact eastern point on the horizon.

In A.D. 389 a wonderful temporary star flashed out near Altair that equalled Venus in brightness and vanished within three weeks' time.

ANTINO[:U]S]

DELPHINUS (del-fi'-nus)--THE DOLPHIN, OR JOB'S COFFIN. (Face Southeast.)

LOCATION.--The little cluster of five stars forming Delphinus is to be seen about 10[deg] northeast of Altair, and, though there are no bright stars in the group, it can hardly escape notice. A line drawn from Vega to Albireo, and prolonged about 20[deg], strikes the star [e] in the tail of the Dolphin. The four other stars of prominence in the constellation are a little above [e], and form a diamond-shaped figure.

The little asterisms Sagitta, the Arrow, and Vulpecula and Anser, the Fox and Goose, are shown just above Delphinus.

Delphinus is also called Job's Coffin. The origin of this appellation is unknown.

In Greece, Delphinus was the Sacred Fish, the sky emblem of philanthropy. The Arabs called it the "Riding Camel."

The star [g] Delphini is a fine double for a small telescope with a marked and beautiful contrast of colors.

The names for [a] and [b] reversed spell "Nicolaus Venator," the Latinized name of the assistant to the astronomer Piazzi.

SAGITTARIUS (saj-i-t[=a]-ri-us)--THE ARCHER. (Face South.)

LOCATION.--A line drawn from Deneb, in Cygnus, to Altair, in Aquila, and prolonged an equal distance, terminates in Sagittarius about 10[deg] east of its distinguishing characteristic, the Milk Dipper. Sagittarius is one of the signs of the zodiac, and lies between Capricornus, on the east, and Scorpius, on the west.

The bow is easily traced out. [g] marks the arrow's tip.

Note the star [m], which serves to point out the Winter Solstice, where the solstitial colure intersects the ecliptic.

On a clear night, the pretty cluster known as Corona Australis, the Southern Crown, can be seen about 10[deg] below the bowl of the Milk Dipper. Its lucida, the fourth-magnitude star Alfecca Meridiana culminates at 9 P.M., August 13th.

Sagittarius is about due south, in a splendid position for observation, during the month of July, between the hours of nine-thirty and eleven o'clock P.M.

Observe with an opera-glass the fine clusters 20 M. and 8 M., also an almost circular black void near the stars [g] and [d], and to the east of this spot another of narrow crescent form.

The stars [ph] and [z] in the Milk Dipper are moving in opposite directions. Future generations therefore will not have this time-honored figure to guide them in locating the Archer in their summer night skies.

OPHIUCHUS (of-i-[=u]-kus)--THE SERPENT BEARER, AND SERPENS. (Face Southwest.)

LOCATION.--A line drawn from [e] Delphini to [g] Aquilae, prolonged about 30[deg], strikes the star Ras Alhague, the brightest star in the constellation and the head of Ophiuchus. It is at one angle of an isosceles triangle, of which Altair is at the apex, and Vega the third angle.

Two constellations are here combined. Ophiuchus is represented as an old man, holding in his hands a writhing serpent.

Ras Algethi, marking the head of Hercules, lies just west of Ras Alhague.

Equally distant southeast and southwest of Ras Alhague are to be seen two stars close together, representing the shoulders of Ophiuchus. His foot rests on the Scorpion just above Antares.

The head of Serpens is the star group in the form of an "X" just below the Crown.

1604 indicates the spot where in that year a famous temporary star appeared, called Kepler's star.

Note the asterism the "Bull of Poniatowski" just east of [g]. The star marked 70 is one of the most distant stars for which a parallax has been obtained. Its distance from the earth = 1,300,000 radii of the earth's orbit, or 120 quadrillion miles.

There is something remarkable in the central position of this gigantic figure. It is situated almost exactly in the mid-heavens, being nearly equidistant from the poles, and midway between the vernal and autumnal equinoxes.

SERPENS]

SCORPIUS (sk[^o]r'-pi-us)--THE SCORPION. (Face South.)

LOCATION.--Scorpius, one of the signs of the zodiac, is a beautiful star group, and one that is easily traced out. It lies just under the Serpent Bearer, between Sagittarius and Libra.

The resemblance to a Scorpion is not difficult to see, hence this constellation is perhaps the most aptly named of any.

The ruddy star Antares, the brightest star in the constellation, is in the heart of the Scorpion. It lies about 40[deg] southwest of Ras Alhague, in Ophiuchus, and a little over 20[deg] west of the bow of Sagittarius. The fact that it is the most brilliant star in this region of the sky renders its identity unmistakable. It is one of the reddest stars in the firmament.

There are several star clusters and double stars to be seen in this constellation. Their position is indicated in the diagram.

The curved tail of the Scorpion is very conspicuous. [l] and [y] are a striking pair and the fine clusters above them can be seen with the naked eye.

A record of a lunar occultation of [b] Scorpii in 295 B.C. is extant.

Note a pair just below [b]. They are known as [[^o]]^1 and [[^o]]^2.

In this region of the sky have appeared many of the brilliant temporary stars, the first one in astronomical annals being discovered in 134 B.C.

Scorpius is mentioned by all the early writers on astronomy and is supposed to be so named because in Egypt it was a sickly time of the year when the sun entered this sign.

LIBRA (l[=i]'-bra)--THE SCALES. (Face Southwest.)

LOCATION.--Libra is one of the signs of the zodiac, and lies between Virgo and Scorpius. Its two chief stars, [a] and [b], may be recognized west of and above the head of the Scorpion.

The star [i] Librae is about 20[deg] northwest of Antares in the Scorpion. Spica in Virgo, a star of the first magnitude, is a little over 20[deg] northwest of [a] Librae.

A quadrilateral is formed by the stars [a], [b], [g], [e], which characterizes the constellation.

The star [a] Librae looks elongated. An opera-glass shows that it has a fifth-magnitude companion.

[b] is a pale green star. Its color is very unusual.

Lyra, Corona, and Hercules are almost directly overhead in the early evening, during July and August, and can best be observed in a reclining position. Thus placed, with an opera-glass to assist the vision, you may study to the best advantage the wonderful sight spread out before you, and search depths only measured by the power of your glass.

When the sun enters the sign Libra the days and nights are equal all over the world and seem to observe a certain equilibrium like a balance, hence the name of the constellation.

CORONA BOREALIS (k[=o]-r[=o]'n[:a] b[=o]-r[=e]-a'-lis)--THE NORTHERN CROWN.

LOCATION.--A line drawn from [a] Cygni, to [a] Lyrae, and projected a little over 40[deg], terminates in the Crown, which lies between Hercules and Bo[:o]tes, and just above the diamond-shaped group of stars in the head of the Serpent.

The characteristic semicircle resembling a crown is easily traced out. The principal stars are of the fourth magnitude excepting Gemma, which is a second-magnitude star and known as the "Pearl of the Crown."

Gemma, sometimes called Alphacca, forms with the stars Seginus and Arcturus, in Bo[:o]tes, an isosceles triangle, the vertex of which is at Arcturus.

Close to [e] a famous temporary appeared suddenly May 12, 1866, as a second-magnitude star. It was known as the "Blaze Star" and was visible to the naked eye only eight days, fading at that time to a tenth-magnitude star, and then rising to an eighth-magnitude, where it still remains.

The native Australians called this constellation "The Boomerang." To the Hebrews it was "Ataroth" and by this name it is known in the East to-day. No two of the seven stars composing the Crown are moving in the same direction or at the same rate.

[a] Coronae is seventy-eight light years distant and sixty times brighter than the sun.

HERCULES (her'-k[=u]-l[=e]z)--THE KNEELER.

LOCATION.--A line drawn from either Vega, in Lyra, or Altair, in Aquila, to Gemma, in Corona Borealis, passes through this constellation. The left foot of Hercules rests on the head of Draco, on the north, and his head nearly touches the head of Ophiuchus on the south.

The star in the head of Hercules, Ras Algethi, is about 25[deg] southeast of Corona Borealis.

[a] Ophiuchi and [a] Herculis are only about 5[deg] apart.

The cluster 13 M., the Halley Nebula, can be easily seen in an opera-glass. In a recent photograph of this cluster 50,000 stars are shown in an area of sky which would be entirely covered by the full moon.

Hercules occupies the part of the heavens toward which the sun is bearing the earth and planets at the rate of twelve miles a second or 373 million miles a year.

On a clear night the asterism Cerberus, the three-headed dog, which Hercules holds in his hand, can be seen.

This constellation is said to have been an object of worship in Phoenicia. There is a good deal of mystery about its origin. The ancient Greeks called it "The Phantom" and "The Man upon his Knees."

The stars [e], [z], [[^e]], and [p] form a keystone shaped figure that serves to identify the constellation.

BO[:O]TES (b[=o]-[=o]'t[=e]z)--THE HERDSMAN, OR BEAR DRIVER. (Face West.)

LOCATION.--Bo[:o]tes lies just west of the Crown, and east of Cor Caroli. It may be easily distinguished by the position and splendor of its principal star, Arcturus, which shines with a golden yellow lustre. It is about 35[deg] east of Denebola, in Leo, and nearly as far north of Spica, in Virgo, and forms with these two a large equilateral triangle. A line drawn from [z] to [[^e]] Ursae Majoris and prolonged about 30[deg] locates it, as does one from [d] Herculis to [g] Coronae prolonged its length.

The brightest stars in Bo[:o]tes outline a characteristic kite-shaped figure. Arcturus is mentioned in the Book of Job and is often referred to as "The Star of Job."

Three stars of the fourth magnitude are situated in the right hand. They are about 5[deg] north of [[^e]] Ursae Majoris.

Contrast the color of Arcturus with Spica, Antares, and Vega.

The trapezium [b], [g], [d], and [m], was called "The Female Wolves," by the Arabians; [th], [i], [k] and [l], "The Whelps of the Hyenas." They knew the constellation as "The Vociferator."

Arcturus is the fourth brightest star in the northern hemisphere. It is 1000 times the size of our sun and rushes through space toward Virgo at the astounding rate of ninety miles a second. It is forty light years distant.

The ancient Greeks called this constellation "Lycaon," a name which signifies a Wolf. The Hebrew name for it was "The Barking Dog."

TES]

VIRGO (ver'-g[=o])--THE VIRGIN. (Face West.)

LOCATION.--An imaginary line drawn from Antares in Scorpius through [a] Librae and prolonged a little over 20[deg] strikes Spica, the brightest star in Virgo, which star is about 30[deg] southwest of Arcturus.

Arcturus, Cor Caroli, Denebola, and Spica form a figure about 50[deg] in length, called the Diamond of Virgo.

The equator, ecliptic, and equinoctial colure intersect each other at a point close to the star [[^e]]. This is called the autumnal equinox.

The star [e] is known as the "Grape Gatherer." It is observed to rise just before the sun at vintage time.

Within the rude square formed by Denebola, and [e], [g], and [b], Virginis, the telescope reveals many wonderful nebulae; hence this region of the sky has been called "The Field of the Nebula."

Spica is an extremely beautiful pure white star. It rises a very little south of the exact eastern point on the horizon.

[g] is a fine double star for a small telescope.

Virgo is mentioned by the astronomers of all ages. By the Egyptians it was intended to represent the goddess Isis, and the Greeks knew it as Ceres. Spica represents the ear of corn held in the Virgin's left hand.

CANES VENATICI (k[=a]'-n[=e]z ve-nat'-i-c[=i])--THE HUNTING DOGS. (Face Northwest.)

LOCATION.--Cor Caroli, the bright star in this constellation, when on the meridian is about 17[deg] south of [e] Ursae Majoris. A line drawn from [[^e]] Ursae Majoris, through Berenice's Hair, to Denebola, in Leo, passes through it.

The dogs, Asterion and Chara, are represented as being held in leash by Bo[:o]tes, the herdsman, in his pursuit of the Great Bear.

Cor Caroli is in the southern hound, Chara, and represents the heart of Charles II of England. It is a beautiful double star in a small telescope.

The so-called "Diamond of Virgo," is clearly shown on this plate. It is formed by connecting with lines the stars Cor Caroli, Denebola, Spica, and Arcturus.

The fifth-magnitude star La Superba, about 7[deg] north and 2-1/2[deg] west of Cor Caroli, is especially noteworthy because of the flashing brilliancy of its prismatic rays.

METEORIC SHOWERS.

JULY TO OCTOBER.

The Perseids are of a yellowish color, and move with medium velocity. Their line of flight is from northeast to southwest. They are probably visible for more than a month, from the latter half of July to the last week in August.

The August meteors are known as the "Tears of St. Lawrence."

The Abbreviations under _Characteristics_ are as follows:

v.--very Sl.--Slow Sk.--Streak-leaving meteors. M.--Moderately B.--Bright T.--Train-leaving meteors. Sw.--Swift F.--Faint Sh.--Short meteors.

THE CONSTELLATIONS OF AUTUMN.

N. at 9 o'clock, October first.]

CASSIOPEIA (kas-i-[=o]-p[=e]'-ya)--THE LADY IN THE CHAIR. (Face North.)

LOCATION.--A line drawn from [d] Ursae Majoris, through Polaris, strikes [a] Cassiopeiae. It is situated the same distance from Polaris as Ursa Major, and about midway between Polaris and the zenith in the Milky Way. Cassiopeia is characterized by a zigzag row of stars which form a rude "W," but in mid-autumn, to an observer facing north, the "W" appears more like an "M," and is almost overhead. Note the spot marked 1572. This is where a very famous temporary star appeared in that year. It was bright enough at one time to be seen in full sunshine. The star [[^e]] is sixteen light years distant.

Caph is equidistant from the Pole, and exactly opposite the star Megres in Ursa Major; with [a] Andromedae and [g] Pegasi it marks the equinoctial colure. These stars are known as "The Three Guides."

The chair can be readily traced out; [b], [a], and [g] mark three of the four corners of the back, and [d] and [e], one of the front legs. The word "Bagdei," made up of the letters for the principal stars, assists the memory.

The stars [g] and [b] are pointer stars to a fifth-magnitude star the lucida of the asterism Lacerta, the lizard about 15[deg] from [b].

Cassiopeia makes an excellent illuminated clock. When [b] is above Polaris it is noon, when it is in the west at right angles to its first position it is 6 P.M. At midnight it is on the northern horizon, and at 6 P.M. it is due east.

This is sidereal time which agrees with mean time on March 22d, and gains on the latter at the rate of two hours a month.

CEPHEUS (s[=e]'-f[=u]s) (Face North.)

LOCATION.--A line drawn from [a] to [b] Cassiopeiae and prolonged about 18[deg] strikes [a] Cephei. The nearest bright star west of Polaris is [g] Cephei. Cepheus is an inconspicuous constellation, lying partly in the Milky Way. A view of this constellation through an opera-glass will repay the observer. Cepheus is characterized by a rude square, one side of which is the base of an isosceles triangle. Look for the so-called garnet star [m], probably the reddest star visible to the naked eye in the United States. The star [z] has a blue companion star.

[a] forms an equilateral triangle with Polaris and [e] Cassiopeiae.

It is claimed that Cepheus was known to the Chaldaeans twenty-three centuries before our era.

Surrounding [d], [e], [z], and [l], which mark the king's head, is a vacant space in the Milky Way, similar to the Coal Sack of Cygnus.

About 4[deg] from [g], in the direction of [k] is a pretty pair of sixth-magnitude stars.

Owing to precession, [g], [b], and [a] Cephei will be successively the Pole Star in 4500, 6000, and 7500 A.D. respectively.

[d] is a double whose components are yellow and blue. It is an interesting variable changing from magnitude 3.7 to 4.9 at intervals of 5 days 8 hours 47 minutes. As it is three times as bright at maximum as at minimum and can be observed with the naked eye its variations are well worth observing.

PEGASUS (peg'-a-sus)--THE WINGED HORSE. (Face South.)

LOCATION.--One corner of the Great Square is found by drawing a line from Polaris to Cassiopeia, and prolonging it an equal distance.

The Great Square is a stellar landmark. Three of the corners of the square are marked by stars in Pegasus; the fourth, and northeastern, corner is marked by the star Alpheratz in Andromeda. Each side of the square is about 18[deg] long.

The horse is generally seen upside down, with his fore feet projected up into the sky. Only the head, neck, and fore feet are represented. The star Enif marks the nose.

[p] is an interesting double, easily seen in an opera-glass. All the stars of the Square are approaching us at an inconceivable speed.

The position of the asterism Equus or Equ[=u]leus, the Little Horse, or Horse's Head, is shown in the diagram.

Delphinus, the water jar of Aquarius, and the circlet in the Western Fish, are all in the vicinity of Pegasus, and indicated in the diagram.

The winged horse is found on coins of Corinth 500 to 430 B.C. The Greeks called this constellation [Greek: hippos].

Pegasus seems to have been regarded in Phoenicia and Egypt as the sky emblem of a ship.

Within the area of the Square Argelander counted thirty naked-eye stars.

Note a fine pair in Equ[=u]leus just west of the star Enif in Pegasus.

The position of the equinoctial colure is defined by a line connecting Polaris, [b] Cassiopeiae, [a] Andromedae, and [g] Pegasi.

ANDROMEDA (an-drom'-e-d[:a])--THE CHAINED LADY.

LOCATION.--The star [a] Alpheratz is at the northeastern corner of the great square of Pegasus, one of the stellar landmarks.

Running east from [a], at almost equal distances, are four other stars, two of which are of the second magnitude. The most easterly one is [b] Persei, known as Algol, the famous variable. Lines connecting the stars [g] Andromedae, Algol, and [a] Persei form a right-angled triangle. The right angle is marked by Algol.

The chief object of interest in this constellation is the great nebula, the first to be discovered. It can be seen by the naked eye and it is a fine sight in an opera-glass. Its location is indicated in the diagram.

The star [g] is the radiant point of the Bielid meteors, looked for in November. It is a colored double visible in a 3" glass.

The great nebula has been called the "Queen of the Nebulae." It is said to have been known as far back as A.D. 905, and it was described 986 A.D. as the "Little Cloud."

Andromeda is very favorable for observation in September, low in the eastern sky.

Note the characteristic "Y" shaped asterism known as Gloria Frederika or Frederik's Glory. It lies about at the apex of a nearly isosceles triangle of which a line connecting Alpheratz and [b] Pegasi is the base. A line drawn from [d] to [a] Cassiopeiae and prolonged a little over twice its length points it out.

PERSEUS (per'-s[=u]s)--THE CHAMPION. (Face Northeast.)

LOCATION.--[a] Persei lies on a line drawn from [b] to [g] Andromedae, and is about 9[deg] from the latter. The most striking feature in Perseus is the so-called "segment of Perseus," a curve of stars beginning about 12[deg] below Cassiopeia, and curving toward Ursa Major. Note the famous variable Algol the Demon star. It represents the Medusa's head which Perseus holds in his hand. It varies from the second to the fourth magnitude in about three and one-half hours, and back again in the same time, after which it remains steadily brilliant for two and three-quarters days, when the same change recurs. Algenib and Algol form with [g] Andromedae, a right-angled triangle.

Note a dull red star near Algol, and a pretty pair just above Algenib.

An opera-glass reveals much that is worthy of observation in this region of the sky. It has been said of the clusters between Cassiopeia and Perseus that they form the most striking sidereal spectacle in the northern heavens. They are visible to the naked eye. Algenib never sets in the latitude of New York, just touching the horizon at its lower culmination. It is estimated that Algol is a little over a million miles in diameter, [[^e]] has three faint stars on one side nearly in a line, and one on the other--a miniature representation of Jupiter and his satellites.

Algol, when on the meridian of New York City, is only one tenth of a degree from the zenith point. This remarkable variable has a dark companion star revolving near it obscuring its light in part from us at stated intervals. By means of the spectroscope the speed diameter and mass of this invisible star has been reckoned.

PISCES (pis'[=e]z)--THE FISHES. (Face Southeast.)

LOCATION.--This constellation is represented by two fishes each with a ribbon tied to its tail. One, the Northern Fish, lies just below [b] Andromedae,--the other, represented by the circlet, is just below Pegasus. The ribbons, represented by streams of faint stars, from a "V" with elongated sides, and terminate in the star Al Rischa, The Knot.

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A Field Book of the StarsChapter I: Part 1

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