The eclipses announce extraordinary events (II)
In the previous texts we have seen how some people believe that the stars fall as a result of a witch. But there are also who tries a more scientific explanation.
For example, designed the stars as living beings, we may think they have diseases, they weaken and may even die. Lucretius (99-ca. 55 BC), for example explains it in his poem De Rerum Natura V, vv. 751-770):
As due to several causes. For, indeed,
Why should the moon be able to shut out
Earth from the light of sun, and on the side
To earthward thrust her high head under sun,
Opposing dark orb to his glowing beams-
And yet, at same time, one suppose the effect
Could not result from some one other body
Which glides devoid of light forevermore?
Again, why could not sun, in weakened state,
At fixed time for-lose his fires, and then,
When he has passed on along the air
Beyond the regions, hostile to his flames,
That quench and kill his fires, why could not he
Renew his light? And why should earth in turn
Have power to rob the moon of light, and there,
Herself on high, keep the sun hid beneath,
Whilst the moon glideth in her monthly course
Athrough the rigid shadows of the cone?-
And yet, at same time, some one other body
Not have the power to under-pass the moon,
Or glide along above the orb of sun,
Breaking his rays and outspread light asunder?
And still, if moon herself refulgent be
With her own sheen, why could she not at times
In some one quarter of the mighty world
Grow weak and weary, whilst she passeth through
Regions unfriendly to the beams her own?
(Translated by William Ellery Leonard. E. P. Dutton. 1916.)
Solis item quoque defectus lunaeque latebras
pluribus e causis fieri tibi posse putandumst.
nam cur luna queat terram secludere solis
lumine et a terris altum caput obstruere ei,
obiciens caecum radiis ardentibus orbem,
tempore eodem aliut facere id non posse putetur
corpus, quod cassum labatur lumine semper?
solque suos etiam dimittere languidus ignis
tempore cur certo nequeat recreareque lumen,
cum loca praeteriit flammis infesta per auras,
quae faciunt ignis interstingui atque perire?
et cur terra queat lunam spoliare vicissim
lumine et oppressum solem super ipsa tenere,
menstrua dum rigidas coni perlabitur umbras,
tempore eodem aliud nequeat succurrere lunae
corpus vel supra solis perlabier orbem,
quod radios inter rumpat lumenque profusum?
et tamen ipsa suo si fulget luna nitore,
cur nequeat certa mundi languescere parte,
dum loca luminibus propriis inimica per exit?
menstrua dum rigidas coni perlabitur umbras.
A similar idea is that the philosopher Diogenes Laertius assigns to Leucipus in Lives and Opinions of Eminent Philosophers, IX, 33
…Eclipses of the sun are rare; eclipses of the moon constantly occur, and this because their orbits are unequal. As the world is born, so, too, it grows, decays and perishes, in virtue of some necessity, the nature of which he does specify.
It is curious the view of Manilius, astronomical poet, when he says that the stars lose their strength during eclipses, in his Astronomy, IV, verses 841-852:
The reason is clear because moon, suffering eclipse in some signs and deprived of her brother [Phoebus, the sun] and plunged into the darkness of the night, when the earth comes between and intercepts the rays of Phoebus and Delia [the moon] does not attract the light wherewith she shines usually, also those signs [zodiacal, eg. effective] languish along with their planet [the moon] and arching at the same time and losing their customary power, mourn Phoebe as though she was at her burial.
The cause itself is reflected in its name: the ancients called them "ecliptic" signs. However, signs suffer while in pairs, and not those who are neighbors, but those who shine in opposite places, like the moon is eclipsed on her circle only when it does not see Phoebus running in the opposite sign .
causa patet, quod, Luna quibus defecit in astris
orba sui fratris noctisque immersa tenebris,
cum medius Phoebi radios intercipit orbis
nec trahit assuetum quo fulget Delia lumen,
haec quoque signa suo pariter cum sidere languent
incurvata simul solitoque exempta vigori
et velut elatam Phoeben in funere lugent.
ipsa docet titulo se causa: ecliptica signa
dixere antiqui. pariter sed bina laborant,
nec vicina loco sed quae contraria fulgent,
sicut Luna suo tum tantum deficit orbe
cum Phoebum adversis currentem non videt astris.
Of course, some found the scientific explanation, they offer us very clearly: the eclipses are caused by the interposition of the moon or earth between the sun and the star that eclipses. This is the key theory in antiquity and so they are many authors that expose it. We will cite a few:
Aristotle uses this theory to prove that the stars are spherical, because the shadow cast by the Earth on the moon can be seen that way; in his On the Heavens, (De caelo,) II, 11, 291b24:
Moreover astronomical arguments give additional confirmation; why no other hypothesis explains the form of increased disk of solar eclipses. Therefore, if any one of the stars is spherical, it is obviously necessary that the rest stars will be spherical also.
Geminus (I century BC.), in his Introduction to the phenomena (of Aratus), Chapter X , speaks of solar eclipses and in XI of lunar eclipses.
Geminus, Introduction to the Phenomena, X, XI:
The eclipses of the Sun occur because of the interposition of the Moon. Because the Sun moves higher and the Moon lower, when the Sun and Moon are at the same degree, the Moon passing under the sun, blocks the sun's rays coming toward our direction. Therefore, we should not speak of them properly as eclipses, but rather as interposition. Indeed, one part of the sun is never eclipsed; it becomes invisible to us through the interposition of the Moon.
That the sun is eclipsed because the interposition of the Moon is the greatest proof that eclipses do not occur on another day, but only 30th, when the Moon is in conjunction with the Sun, and since then the magnitude of the eclipse is due to the geographical locations.
Eclipses of Moon are caused by the incidence of the Moon on the shadow casted by the Earth. Just as the other bodies illuminated by the sun cast shadows, so the Earth, illuminated by the sun casts a shadow. In addition it occurs that, because of the size of the Earth, the shadow is evident and profound.
When the Moon is diametrically opposite to the Sun, then the shadow casted by the Earth is also diametrically opposed to the Sun; therefore the moon, when it moves closer than the shadow falls logically in the shadow casted by the Earth.
The portion of the moon which affects the Earth's shadow is always deprived of sunlight because of the interposition of the earth; therefore at this moment they are at the same line the Sun, the Earth, the shadow of the Earth and the Moon. Therefore eclipses of Moon do not occur on another day, but on the full moon; therefore the moon is diametrically opposite to the sun.
The Hispanic Roman Higinus (64 BC-17 AD), who according to Luis Vives was born in Valencia and who has given his name to one of the lunar craters, also proposes this theory in his Astronomy, IV, 14, 3:
You can also understand what happens. As when someone approaches his flat hand to his eyes, if closer it is, less he can see, and if farther away it is, more all things will appear to him. Similarly when the moon reaches the position of the sun, then it seems to be near it and obstructs its rays, and it can not eject its light. However, when the moon is far from that place, then the sun casts its light, and so it comes knocking on our bodies.The lunar eclipse therefore occurs when the moon is near by its size and the sun runs below the earth. Thus, if you drew a straight line down the middle of the earth , the line could touch the sun under the earth and the moon above the earth. When this happens, necessarily sunlight, by the magnitude of the earth, are deflected, so that its light, with which the moon looks, can not get to it, and so it is thought to produce the eclipse of moon.
Quod evenire sic etiam potest intellegi. Ut si quis alicui manum planam ad oculos admoverit, quanto magis sic fecerit, hoc minus ille videre poterit; et quanto longius ab eo discesserit, hoc magis illi omnia poterunt apparere. Simili ratione cum luna ad solis locum pervenit, tunc proxima eius videtur esse et radios eius obturare, ut lumen eicere non possit. Cum autem luna ab eo loco discesserit, tunc sol lumen eicit, et ita ad corpora nostra adicit.
Lunae autem eclipsis sic evenit, cum prope dimensione sit luna, cum abierit sol sub terram, dumtaxat hoc modo, ut per mediam terram si quid directum traieceris, contingere possit solem sub terra, lunam autem supra terram; quod cum ita evenit, necesse est solis radios propter magnitudinem terrae ita esse dimissos, ut lumen eius, quo luna lucet, non possit ad eam pervenire, et ita existimatur fieri eclipsis lunae.
Also Pliny the Elder (AD 62-113) gives this explanation in his Natural History, II, 7, 47:
For it is evident that the sun is hid by the intervention of the moon, and the moon by the opposition of the earth, and that these changes are mutual, the moon, by her interposition, taking the rays of the sun from the earth, and the earth from the moon. As she advances darkness is suddenly produced, and again the sun is obscured by her shade; for night is nothing more than the shade of the earth. The figure of this shade is like that of a pyramid or an inverted top; and the moon enters it only near its point, and it does not exceed the height of the moon, for there is no other star which is obscured in the same manner, while a figure of this kind always terminates in a point. (Translated by John Bostock, M.D., F.R.S. H.T. Riley, Esq., B.A. London. Taylor and Francis, Red Lion Court, Fleet Street. 1855.)
Quippe manifestum est solem interuentu lunae occultari lunamque terrae obiectu ac uices reddi, eosdem solis radios luna interpositu suo auferente terrae terraque lunae. Hac subeunte repentinas obduci tenebras rursumque illius umbra sidus hebetari. Neque aliud esse noctem quam terrae umbram, figuram autem umbrae similem metae ac turbini inuerso, quando mucrone tantum ingruat neque lunae excedat altitudinem, quoniam nullum aliud sidus eodem modo obscuretur et talis figura semper mucrone deficiat.
The ancients were aware of the danger involved directly observing the eclipses of the sun, which can cause irreversible blindness. So Plato (ca. 427-347 BC) in his dialogue Phaedo, 99d tells us:
SOCRATES: do you wish me, Cebes,” said he, “to give you an account of the way in which I have conducted my second voyage in quest of the cause?”
“I wish it with all my heart,” he replied.
“After this, then,” said he, “since I had given up investigating realities, I decided that I must be careful not to suffer the misfortune which happens to people who look at the sun and watch it during an eclipse. For some of them ruin their eyes unless they look at its image in water or something of the sort. I thought of that danger, and I was afraid my soul would be blinded if I looked at things with my eyes and tried to grasp them with any of my senses. (Translated by Harold North Fowler)
Seneca also reminds us how we must observe the eclipse of Sun:
Whenever we wish to observe an eclipse of the sun, we place on the ground basins filled with oil or pitch. The thick liquid is not easily disturbed, and therefore retains the images it receives. Images, I may observe, cannot be seen except in a liquid at rest. Then we are in the habit of noting how the moon obstructs the sun, and by the interposition of her body hides his, which is so much larger, sometimes partially, if it so fall out that she only encounter a portion of his orb, sometimes completely. The latter is called a total eclipse : it quite shuts out the light and shows us the stars ; it occurs when the centre of the two bodies lies in the same straight line. ( Translation by John Clarke, M.A., 1910)
[12,1] Quotiens defectionem solis uolumus deprehendere, ponimus pelues, quas aut oleo aut pice implemus, quia pinguis umor minus facile turbatur et ideo quas recipit imagines seruat; apparere autem imagines non possunt nisi in liquido et immoto. Tunc solemus notare, quemadmodum luna soli se opponat et illum tanto maiorem obiecto corpore abscondat, modo ex parte, si ita competit, ut in latus eius incurreret, modo totum; haec dicitur perfecta defectio, quae stellas quoque ostendit et intercipit lucem, tunc scilicet cum uterque orbis sub eodem libramento stetit.
They say that Thales was the first to predict an eclipse that have taken place in 585 BC but he had announced a year earlier. Current astronomers consider this prediction impossible and the news as a result of a somewhat hagiographic view of Thales.
Herodotus tells us (ca. 639-ca. 547 BC) in Book I of his history: the kings of Lydia and Media, terrorized by the same eclipse, signed an armistice as soon as their armies were ready to engage. Both monarchs interpreted the darkness of the sun as a sign from heaven to end hostilities.
Herodotus, The Stories, I, 74
After this, since Alyattes would not give up the Scythians to Cyaxares at his demand, there was war between the Lydians and the Medes for five years; each won many victories over the other, and once they fought a battle by night.
They were still warring with equal success, when it happened, at an encounter which occurred in the sixth year, that during the battle the day was suddenly turned to night. Thales of Miletus had foretold this loss of daylight to the Ionians, fixing it within the year in which the change did indeed happen.
So when the Lydians and Medes saw the day turned to night, they stopped fighting, and both were the more eager to make peace. Those who reconciled them were Syennesis the Cilician and Labynetus the Babylonian; (Translated by A.D. Godley)
It was this question of predictability certainly an issue that impassioned ancients.
At the beginning of the article I commented the discovery of the famous cycle "Saros" that the Greeks took from the Babylonians, and I give two texts, from Pliny and from Ptolemy, to corroborate his knowledge.
Pliny referred to Hipparchus (ca.190-120 BC) as the astronomer who understood these cycles. Strabo in his Geography, I, 1, 13 says about Hipparcus:
Many have testified to the amount of knowledge which this subject requires, and Hipparchus, in his Strictures on Eratosthenes, well observes, ‘that no one can become really proficient in geography, either as a private individual or as a professor, without an acquaintance with astronomy, and a knowledge of eclipses. For instance, no one could tell whether Alexandria in Egypt were north or south of Babylon, nor yet the intervening distance, without observing the latitudes.43 Again, the only means we possess of becoming acquainted with the longitudes of different places is afforded by the eclipses of the sun and moon.’ Such are the very words of Hipparchus. (H.C. Hamilton, Esq., W. Falconer, M.A., Ed. 1903).
Cicero (106-43 BC) also says that eclipses (of Moon) were provided in advance by studying the regular motions of the Moon in De divinatione II, 17
"How can anything be foreseen that has no cause and no distinguishing mark of its coming? Eclipses of the sun and also of the moon are predicted for many years in advance by men who employ mathematics in studying the courses and movements of the heavenly bodies; and the unvarying laws of nature will bring their predictions to pass. Because of the perfectly regular movements of the moon the astronomers calculate when it will be opposite the sun and in the earth's shadow —which is 'the cone of night '1 —and when, necessarily, it will become invisible. For the same reason they know when the moon will be directly between the earth and the sun and thus will hide the light of the sun from our eyes. They know in what sign each planet will be at any given time and at what time each day any constellation will rise and set. You see the course of reasoning followed in arriving at these predictions. (Translated by William Armistead Falconer, 1923)
Qui potest provideri quicquam futurum esse, quod neque causam habet ullam neque notam, cur futurum sit? Solis defectiones itemque lunae praedicuntur in multos annos ab iis, qui siderum motus numeris persequuntur; ea praedicunt enim, quae naturae necessitas perfectura est. Vident ex constantissimo motu lunae, quando illa e regione solis facta incurrat in umbram terrae, quae est meta noctis, ut eam obscurari necesse sit, quandoque eadem luna subiecta atque opposita soli nostris oculis eius lumen obscuret, quo in signo quaeque errantium stellarum quoque tempore futura sit, qui exortus quoque die signi alicuius aut qui occasus futurus sit. Haec qui ante dicunt, quam rationem sequantur, vides.
The famous mechanical device known as the Antikythera Mechanism, dating from 87 BC, we will discussed about it on another occasion, is a kind of gear-based calculator to predict the position of the Sun, the Moon and some planets. It allowed to calculate the cycle "saros" I was talking about at the beginning and therefore it helped to provide for the existence of eclipses.
The determination of these cycles like "saros", the millennial observation of the movements, creating instruments to reproduce the movements of the stars, all provided them great experience and made them walk in the right direction and from Mesopotamia, especially referring to the eclipses of moon; but experts agree in saying that the instruments available at this time were unable to set in advance and accurately the occurrence of an eclipse. Only very recently it has achieved great precision in this regard.
In any case, astronomy (astrology) enjoyed great recognition in antiquity. Indeed, attempts to explain the stars and their movements, theoretical speculations and practices that incorporate and develop knowledge of mathematics and geometry, are a real scientific endeavor.
Pliny, whom we have mentioned several times, extols science and courage of the men trying to find out the causes of things. In the passage quoted above in relation to Sulpicius Galus before the battle of Pydna, he follows commenting:
Pliny, Natural History II, 9 (12) (54)
These were indeed great men, superior to ordinary mortals, who having discovered the laws of these divine bodies, relieved the miserable mind of man from the fear which he had of eclipses, as foretelling some dreadful events or the destruction of the stars. This alarm is freely acknowledged in the sublime strains of Stesichorus and Pindar, as being produced by an eclipse of the sun. And with respect to the eclipse of the moon, mortals impute it to witchcraft, and therefore endeavour to aid her by producing discordant sounds. In consequence of this kind of terror it was that Nicias, the general of the Athenians, being ignorant of the cause, was afraid to lead out the fleet, and brought great distress on his troops. Hail to your genius, ye interpreters of heaven! ye who comprehend the nature of things, and who have discovered a mode of reasoning by which ye have conquered both gods and men! For who is there, in observing these things and seeing the labours which the stars are compelled to undergo (since we have chosen to apply this term to them), that would not cheerfully submit to his fate, as one born to die? I shall now, in a brief and summary manner, touch on those points in which we are agreed, giving the reasons where it is necessary to do so; for this is not a work of profound argument, nor is it less wonderful to be able to suggest a probable cause for everything, than to give a complete account of a few of them only. ( John Bostock, M.D., F.R.S. H.T. Riley, Esq., B.A. London.)
viri ingentes supraque mortalia, tantorum numinum lege deprehensa et misera hominum mente iam soluta, in defectibus scelera aut mortem aliquam siderum pavente — quo in metu fuisse Stesichori et Pindari vatum sublimia ora palam est deliquio solis — aut in luna veneficia arguente mortalitate et ob id crepitu dissono auxiliante — quo pavore ignarus causae Nicias Atheniensium imperator veritus classem portu educere opes eorum adflixit —: macte ingenio este, caeli interpretes rerumque naturae capaces, argumenti repertores, quo deos hominesque vicistis! quis enim haec cernens et statos siderum (quoniam ita appellare placuit) labores non suae necessitati mortales genitos ignoscat?
Nunc confessa de iisdem breviter atque capitulatim attingam ratione admodum necessariis locis strictimque reddita, nam neque instituti operis talis argumentatio est neque omnium rerum afferri posse causas minus mirum est quam constare in aliquis.
Ovid also appreciates the extraordinary courage of those who studied the stars, in Fasti, I, 295 et seq .:
What is to stop me if I should tell also of the stars, their risings and their settings? That was part of my promise. Ah happy souls, who first took thought to know these things and scale the heavenly mansions! Well may we believe they lifted up their heads alike above the frailties and the homes of men. Their lofty natures neither love nor wine did breaks, nor civil business nor the toils of war; no low ambition tempted them, nor glory’s tinsel sheen, nor lust of hoarded pelf. The distant stars they brought within our ken, and heaven itself made subject to their wit. So man may reach the sky: no need that Ossa on Olympus should be piled, and that Pelion’s peak should touch the topmost stars. Under these leaders we, too, will plum the sky and give their own days to the wandering signs. (Translated by Frazer, James George. Loeb Classical Library)
Quis vetat et stellas, ut quaeque oriturque caditque,
dicere? promissi pars fuit ista mei.
felices animae, quibus haec cognoscere primis
inque domus superas scandere cura fuit!
credibile est illos pariter vitiisque locisque
altius humanis exeruisse caput.
non Venus et vinum sublimia pectora fregit
officiumque fori militiaeve labor;
nec levis ambitio perfusaque gloria fuco
magnarumque fames sollicitavit opum.
admovere oculis distantia sidera nostris
aetheraque ingenio supposuere suo.
sic petitur caelum: non ut ferat Ossan Olympus,
summaque Peliacus sidera tangat apex.
nos quoque sub ducibus caelum metabimur illis
ponemusque suos ad vaga signa dies.
In the classic texts there are numerous references to eclipses actually incurred. I pick up some from article “La explicación de los eclipses en la Antigüedad Grecolatina”("The explanation of eclipses in Greco-Latin antiquity") of the authors Roberto Casazza Alejandro Gangui ,University of Buenos Aires, who in turn cite Couderc, 1969: 128-134. They are considered historic or described by reliable historical sources the following :: Assyrian eclipse canon (June 15, 763 BC); eclipse of Ashurbanipal (June 27, 661 BC); eclipse of Archilochus (April 6, 648 B.C.); eclipse of Thales (May 28, 585 BC) (-there dense discussions of this eclipse); eclipse of Pindar (April 30, 463 BC); eclipse of Thucydides (August 3, 431 B.C.); eclipse of Agatocles (August 15, 310 BC); eclipse of Hipparchus (November 20 129 BC); eclipse of Phlegon (November 24, 29 A.D.); eclipse of Plutarch (March 20, 71 A.D.); eclipse of Theon (June 16, 364 AD Here are also doubtfully). Quoted from Couderc, 1969: 128-134.