ASTRONO´MIA
ASTRONO´MIA astronomy. It is not proposed in the
present article to give a technical history of the rise and progress of
astronomy among the ancients, but to confine ourselves to what may be
regarded as the popular portion of the science,--the observations, namely,
upon the relative position and apparent movements of the celestial bodies,
especially the fixed stars, which from the earliest epoch engaged the
attention of those classes of men who, as shepherds or mariners, were wont
to pass their nights in the open air. We shall consider :--
- 1. The different names by which the constellations were
distinguished among the Greeks and Romans, and the legends attached
to each; but we shall not attempt to investigate at length the
origin of these names, nor the times and places when and where they
were first bestowed. The materials for this first section have been
carefully collected by Ideler in his essay entitled
Untersuchungen über den Ursprung und die
Bedeutung der Sternnamen (Berlin, 1809), a work which we
now mention specially once for all to avoid the necessity of
constant references; in the Historische Untersuchungen
über die astronomischen Beobachtungen der
Alten, by the same author (Berlin, 1806); in a paper by
Buttmann, Ueber die Entstehung der Sternbilder auf der
griechischen Sfäre, contained in the
Transactions of the Berlin Academy for 1826; in Delambre,
Hist. de l'Astr. Ancienne; and in the
Geschichte der Astronomie of Schaubach.
- 2. The risings and settings of the fixed stars considered with
reference to the position of the sun in the ecliptic,--a series of
phenomena which, recurring regularly every tropical year, served in
the most remote ages as the sole guides for the operations of the
husbandman, and which, being in later times frequently appealed to
by the poets, are sometimes designated the “Poetical Risings
and Settings of the Stars.” Here we chiefly depend upon
the compilations and dissertations, ancient and modern, brought
together in the Uranologion of Petavius; upon the
disquisition by J. F. Pfaff entitled Commentatio de Ortibus
et Occasibus Siderum apud auctores classicos
commemoratis (Gotting. 1786); upon a paper by Ideler,
Ueber den astronomischen Theil der Fasti des
Ovid, in the Transactions of the Berlin Academy for
1822-1823, and on the Handbuch der Chronologie by the
same author.
- 3. The division of the year into two, three, or more seasons,
according to the risings and, settings of particular stars or
clusters of stars. The Handbuch der Chronologie
contains a full examination of all the most important passages from
the Greek and Roman authors which bear upon these points. The
determination of the length of the year, and the distribution of
time into months, days, hours, and other periods, which in some
degree belong to the same subject, are treated of separately
under the heads of CALENDARIUM and DIES; and
confining our attention for the present to the fixed stars, we
shall make a few remarks on the bodies of the solar system under
PLANETAE
The history and names of the constellations.
The only constellations known to Homer
Hom. Il.
18.485-
489;
Od. 5.272-
275) appear to have been the
Great Bear or
Waggon, Boötes, and
Orion, with the two clusters of the
Hyades and
Pleiades. Hesiod
mentions the Pleiades (
Op. et Di. 383),
Arcturus (possibly for
Boötes; see below: ib. 566),
Sirius (repeatedly), the
Hyades (
Op. 615), and
Orion (
Op. 598, &c.).
Pliny (
H. IV. 2.31) attributes the invention of the signs
of the zodiac to Cleostratus of Tenedos (fl. B.C. 500), and asserts that
Aries and
Sagittarius
were marked out before the rest. Aristotle more than once mentions
ὁ κύκλος τῶν ζῳδίων. The first
distinct information with regard to the Grecian heavens was contained in
the
Ἔνοπτρον and the
φαινόμενα of Eudoxus of Cnidus, who died
B.C. 352. Both of these works are, it is true, lost with the exception
of a few fragments (cf.
Papyrus Grecs du Museé du
Louvre, pp. 7-76; Paris, 1860), but their contents are known
to us from the poem of Aratus (fl. B.C. 260), which, as we are assured
in the commentary which bears the name of Hipparchus, does little more
than represent in verse, with very few variations, the matter contained
in the two treatises named above, especially in the latter. The great
popularity enjoyed by the production of Aratus ( “Cum sole et luna
semper Aratus erit,”
Ov. Am. 1.15,
16) must have depended upon the attractions presented by his
theme, and certainly not upon the spirit or grace with which that theme
was handled. We know the names
[p. 1.215]of thirty-five
Greeks who composed commentaries upon it, and we are acquainted with no
less than three translations into Latin verse--one by Cicero, of which
fragments only remain; another by Caesar Germanicus, of which a
considerable portion has been preserved; and a third by Rufus Festus
Avienus, which is entire. Virgil borrowed largely from this source in
those portions of his Georgics which contain references to the heavenly
bodies, and particularly in that section which is devoted to prognostics
of the weather. There are also valuable Greek scholia ascribed to the
younger Theon, but manifestly compounded of materials derived from many
different quarters. The work itself is divided into three parts:
- 1. A description of the constellations, extending to line 452.
- 2. A short account of the Planets, of the Milky Way, of the
Tropical Circles, and of the Equator, followed from 5.559 by a
full detail of the stars which rise and set as each sign of the
zodiac appears in succession (συνανατολαί).
- 3. At line 733 commences what is frequently regarded as a
separate poem, and placed apart under the title Διοσημεῖα, consisting of a
collection of the various appearances which enable an observer
of nature to predict the weather. It will be seen below that the
constellations described by Aratus still retain, with a few
variations, the names by which he distinguishes them.
In a little tract ascribed to Eratosthenes (fl. B.C. 230), entitled
Καταστερισμοί, probably an
abridgment of a more complete treatise, in which he details the
mythological origin of the constellations, together with the number and
place of the stars in each, we find the same forms arranged in the same
order as in Aratus, who is followed step by step. The
Bird, however, is here termed the
Swan ;
the
Centaur is individualised into
Chiron; and the
Hair of Berenice appears
for the first time, having been introduced by Conon in honour of the
sister-wife of Ptolemy Euergetes.
Scientific astronomy commenced at Alexandria in the early part of the
third century before our era; and the first steps were made by
Timocharis and Aristyllus, who flourished about B.C. 290. They invented
the method of determining the places of the fixed stars, by referring
them to one of the great circles of the heavens, and for this purpose
selected the equator. By them, as we learn from Ptolemy, the right
ascension and declination of many stars were observed, among others of
Spica in the Virgin, which they found
to be 8° from the equinox of autumn.
Hipparchus, about 150 years later, followed up the track which they had
indicated: his observations extended from B.C. 162 to B.C. 127; and,
whether we regard the originality, the magnitude, or the importance of
his labours, he is well entitled to be regarded as the father of the
science. (See
Plin. Nat. 2.95.) In
addition to many other services, he first drew up a regular catalogue of
the fixed stars, pointing out their position and magnitude; he first
delineated accurately the shape of the constellations; and he first
discovered the precession of the equinoxes by comparing his own
observations with those of Timocharis and Aristyllus. It is much to be
lamented that all the works of so great a man should have perished, with
the exception of a commentary in three books upon the description of the
fixed stars by Eudoxus and Aratus (
Ἐξήγησις
τῶν Ἀράτου καὶ Εὐδόξου φαινομένων the least
valuable perhaps of all his productions. We have, however, every reason
to believe that the substance of his most valuable observations has been
preserved in the Almagest of Ptolemy, which long enjoyed such high fame
that all former authors were allowed to sink into oblivion.
The catalogue of the fixed stars by Ptolemy (fl. A.D. 150), contained in
the seventh and eighth books of the Almagest, and derived in all
probability in a great measure from that compiled by Hipparchus, long
served as the model for all subsequent labours in the same field, and
little more than two centuries have elapsed since any attempt was made
to supersede it by something more perfect. It embraces 48 constellations
(21 northern, 15 southern, and the 12 signs of the zodiac), comprising
15 stars of the first magnitude, 45 of the second, 208 of the third, 474
of the fourth, 217 of the fifth, 49 of the sixth, 9 obscure, and 5
nebulous, in all 1022. These are the constellations, usually denominated
the
Old Constellations, to distinguish them from the
additions made in modern times, and these we shall consider in regular
order. The stars are enumerated according to the place which they occupy
in the figures; the latitude, longitude, and magnitude of each being
specified. In connexion with many constellations, several stars are
mentioned as
ἀμόρφωτοι,--that is, not
included within the limits of any one of the figures; among those near
the Lion he notices the
Hair of Berenice, among those
near the Eagle the
Antinous. The single stars and small
groups to which particular names are assigned are,
Arcturus, the
Lyre, Capella,
the
Kids, the
Eagle, the
Hyades, the
Pleiades, the
Manger, the
Asses, Regulus (
βασιλίσκος),
Vindemiatrix, Spica, Antares,
the
Hound (he does not give the name
Sirius),
Canopus, and
Procyon.
Among our Greek authorities we must not pass over Geminus, whose work
Εἰσαγωγὴ εἰς τὰ φαινόμενα
contains in sixteen chapters an exposition of the most striking facts in
astronomy and mathematical geography. We know nothing of him personally;
but it has been inferred from his book that he was a native of Rhodes,
and that he flourished about B.C. 70 at Rome, or at some place under the
same parallel. The second chapter treats of the constellations and of
those stars and small clusters distinguished by particular names. The
Coma Berenices, which is not included
in the 21 northern constellations of Ptolemy, has here an independent
place assigned to it; the
Foal, or
Little
Horse, is termed
προτομὴ ἵππου καθ̓
Ἵππαρχον, which seems to indicate that it was
introduced by Hipparchus; in addition to the 15 southern constellations
of Ptolemy, we find the
Stream (
χύσις ὕδατος) issuing from the urn of Aquarius, and
the
Thyrsus of the Centaur. The sixteenth
chapter is particularly interesting and valuable, since it contains a
parapegma or calendar of the risings and settings of the fixed stars,
with prognostics of the weather, according to Meton, Euctemon, Eudoxus,
Callippus, and others, the observations of each being quoted separately.
The Romans adopted the knowledge of the stars communicated by the Greeks
without in the slightest degree extending it. Only two
[p. 1.216]Latin writers discourse specially on the subject, Manilius
and Julius Firmicus, and their treatises belong rather to Judicial
Astrology. The poets, however, especially Ovid and Virgil, make frequent
allusions to the risings and settings of the fixed stars, to the most
remarkable constellations and to the legends attached to them. Cicero,
Germanicus, ant Avienus, as we have stated above, executed translations
of Aratus; while in Vitruvius, Pliny, Columella, Martianus Capella, the
Scholiast on Germanicus, and Hyginus, we find a multitude of details.
Manilius, it is clear, took Aratus for his guide in so far as the
constellations were concerned ; for he does not notice the
Hair
of Berenice, the
Foal, nor the
Southern Crown.
Pliny speaks of the constellations as seventy-two in number; but he seems
to have eked out the sum by counting separately portions of figures,
such as the
Pleiades, the
Hyades, the
Urn and the
Stream of Aquarius, the
Thyrsus of the
Centaur, the
Head of Medusa, the
Scimetar of Perseus, the
Manger, the
Two Asses, Capella, the
Kids, the
Hair of Berenice, the
Throne of
Caesar, and probably the more conspicuous among the individual
stars, such as
Arcturus and
Sirius. He sets down the number of observed
stars at 1600, which far exceeds the catalogue of Ptolemy.
The Scholia on Germanicus do not constitute a regular commentary like the
Scholia on Aratus, but are translations from Eratosthenes, with some
excerpts, added subsequently perhaps, from the
Sphaera Graeca et Barbara of Nigidius Figulus and other
works on astronomical myths.
The
Poéticon Astronomicon, which bears the name
of Hyginus, is written in the style of Eratosthenes, and is in a great
measure borrowed from him. No notice is here taken of the
Foal nor of the
Southern Crown, which
proves that at the time when it was composed, whenever that may have
been, more attention was paid to Aratus than to Hipparchus and Ptolemy.
Names of the Constellations.
In what follows we arrange the constellations, with one or two
trifling exceptions, in the order adopted by Ptolemy, enumerating
first the twenty-one northern signs ; secondly, the twelve zodiacal
signs; and lastly, the fifteen southern signs. In each case we give,
first, the name by which the constellation is known among ourselves
; secondly, the name ascribed to it by Aratus; and lastly, the other
Greek and Latin names which most frequently occur or which deserve
particular notice.
Northern Signs.
1. The Great Bear, The Plough, Charles' Wain
Ἄρκτος (
μεγάλη),
Ἑλίκη (Arat. 27, &c.),
Major Arctus, Major Ursa (German.),
Helice (Cic., Manil.
1.303). The most remarkable cluster in the northern
hemisphere, both on account of its brilliancy and from the
circumstance that it never sinks below the horizon in Europe
and those parts of Asia known to the ancients, is that which
as early as the time of Homer was known by the names of
Ἄρκτος,
The She Bear, or
Ἅμαξα,
The Waggon (
Il.
18.487 ;
Od.
5.275), which the Romans translated by the equivalent
terms
Ursa and
Piaustrum or
Currus. At a later period when the Lesser Bear
had been added to the number of the celestial signs, the
epithets
