Eclipse of Thales

Last updated

Eclipse occurred 28 May 585 BC SoFi-584-05-28.gif
Eclipse occurred 28 May 585 BC

The eclipse of Thales was a solar eclipse that was, according to ancient Greek historian Herodotus, accurately predicted by the Greek philosopher Thales of Miletus. If Herodotus' account is accurate, this eclipse is the earliest recorded as being known in advance of its occurrence. Many historians believe that the predicted eclipse was the solar eclipse of 28 May 585 BC. [1] [2] How exactly Thales predicted the eclipse remains uncertain; some scholars assert the eclipse was never predicted at all. [3] [4] [5] Others have argued for different dates, [6] but only the eclipse of May 585 BC matches the conditions of visibility necessary to explain the historical event. [7]

Contents

According to Herodotus, the appearance of the eclipse was interpreted as an omen, and interrupted a battle in a long-standing war between the Medes and the Lydians. American writer Isaac Asimov described this battle as the earliest historical event whose date is known with precision to the day, and called the prediction "the birth of science". [8]

The eclipse

The eclipse peaked over the Atlantic Ocean at 37°54′N46°12′W / 37.9°N 46.2°W / 37.9; -46.2 (Battle of Halys eclipse peak) and the umbral path reached south-western Anatolia in the evening hours. The Halys River, the presumed site of the battle mentioned by Herodotus, is just within the error margin for ΔT provided. [2]

Herodotus' account

Herodotus' The Histories 1.73–74 states that a war started in that period between the Medes and the Lydians.

Another combat took place in the sixth year, in the course of which, just as the battle was growing warm, day was on a sudden changed into night. This event had been foretold by Thales, the Milesian, who forewarned the Ionians of it, fixing for it the very year in which it actually took place. The Medes and Lydians, when they observed the change, ceased fighting, and were alike anxious to have terms of peace agreed on. [9]

Thales' prediction

While doubt has been cast on the truth of the story, there are other accounts of it besides that of Herodotus. Diogenes Laërtius says that Xenophanes, who lived in the same century as Thales, was impressed with the prediction, and he also gives additional testimonies from the pre-Socratics Democritus and Heraclitus. [6]

Cicero mentions that Thales was the first man to successfully predict a solar eclipse during the reign of Astyages, the last king of the Median empire. [10] Pliny the Elder mentions as well that Thales had predicted a solar eclipse during the reign of Alyattes of Lydia. [11]

At the time of Thales' purported prediction it was not yet known that eclipses were caused by the Moon coming between the Earth and the Sun, a fact that would not be discovered until over a century later by either Anaxagoras or Empedocles. [12]

If the account is true, it has been suggested that Thales would have had to calculate the timing of any eclipse by recognizing patterns in the periodicities of eclipses. [6]

It has been postulated that Thales may have used the Saros cycle in his determination, or that he may have had some knowledge of Babylonian astronomy. However, Babylonians were far from being able to predict the local conditions of solar eclipses at that point, which makes this hypothesis highly unlikely. [4] [13] At the time, there was no known cycle that could be reliably used to predict an eclipse for a given location and, therefore, any accurate prediction would have been down to luck. [5] [6]

See also

Related Research Articles

<span class="mw-page-title-main">Alyattes</span> King of Lydia (c.635 - c.585 BC)

Alyattes, sometimes described as Alyattes I, was the fourth king of the Mermnad dynasty in Lydia, the son of Sadyattes, grandson of Ardys, and great-grandson of Gyges. He died after a reign of 57 years and was succeeded by his son Croesus.

<span class="mw-page-title-main">Hipparchus</span> 2nd-century BC Greek astronomer, geographer and mathematician

Hipparchus was a Greek astronomer, geographer, and mathematician. He is considered the founder of trigonometry, but is most famous for his incidental discovery of the precession of the equinoxes. Hipparchus was born in Nicaea, Bithynia, and probably died on the island of Rhodes, Greece. He is known to have been a working astronomer between 162 and 127 BC.

<span class="mw-page-title-main">Lydia</span> Ancient Anatolian kingdom

Lydia was an Iron Age kingdom of western Asia Minor located generally east of ancient Ionia in the modern western Turkish provinces of Uşak, Manisa and inland Izmir. The ethnic group inhabiting this kingdom are known as the Lydians, and their language, known as Lydian, was a member of the Anatolian branch of the Indo-European language family. The capital of Lydia was Sardis.

<span class="mw-page-title-main">Thales of Miletus</span> Ancient Greek philosopher (c. 624 – c. 545 BC)

Thales of Miletus was an Ancient Greek pre-Socratic philosopher from Miletus in Ionia, Asia Minor. Thales was one of the Seven Sages, founding figures of Ancient Greece, and credited with the saying "know thyself" which was inscribed on the Temple of Apollo at Delphi.

The 6th century BC started on the first day of 600 BC and ended on the last day of 501 BC.

This article concerns the period 589 BC – 580 BC.

The year 585 BC was a year of the pre-Julian Roman calendar. In the Roman Empire, it was known as year 169 Ab urbe condita. The denomination 585 BC for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.

<span class="mw-page-title-main">Croesus</span> King of Lydia

Croesus was the king of Lydia, who reigned from 585 BC until his defeat by the Persian king Cyrus the Great in 547 or 546 BC. According to Herodotus, he reigned 14 years.

<span class="mw-page-title-main">Antikythera mechanism</span> Ancient analogue astronomical computer

The Antikythera mechanism is an Ancient Greek hand-powered orrery, described as the oldest known example of an analogue computer used to predict astronomical positions and eclipses decades in advance. It could also be used to track the four-year cycle of athletic games which was similar to an Olympiad, the cycle of the ancient Olympic Games.

<span class="mw-page-title-main">Cyaxares</span> Ruler of Media

Cyaxares was the third king of the Medes.

Sudines was a Babylonian sage. He is mentioned as one of the famous Chaldean mathematicians and astronomer-astrologers by later Roman writers like Strabo.

The Median empire, also known as the Cyaxarid dynasty, was, according to Herodotus, a dynasty composed of four kings who ruled for 150 years under the Median Empire. If Herodotus' story is true, the Medes were unified by a man named Deioces, the first of the four kings who would rule the Medan Empire, a mighty empire that included large parts of Iran and eastern Anatolia.

<span class="mw-page-title-main">Babylonian astronomy</span> Study of celestial objects during the early history of Mesopotamia

Babylonian astronomy was the study or recording of celestial objects during the early history of Mesopotamia.

<span class="mw-page-title-main">Solar eclipse</span> Natural phenomenon wherein the Sun is obscured by the Moon

A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby obscuring the view of the Sun from a small part of the Earth, totally or partially. Such an alignment occurs approximately every six months, during the eclipse season in its new moon phase, when the Moon's orbital plane is closest to the plane of the Earth's orbit. In a total eclipse, the disk of the Sun is fully obscured by the Moon. In partial and annular eclipses, only part of the Sun is obscured. Unlike a lunar eclipse, which may be viewed from anywhere on the night side of Earth, a solar eclipse can only be viewed from a relatively small area of the world. As such, although total solar eclipses occur somewhere on Earth every 18 months on average, they recur at any given place only once every 360 to 410 years.

<span class="mw-page-title-main">Battle of the Eclipse</span> Part of the Lydo-Median War

The Battle of the Eclipse was fought in the early 6th century BC in Anatolia between the Medes and the Lydians. According to ancient Greek historian Herodotus, the battle was interrupted by "day turning into night" – presumably a solar eclipse – and the result was a draw which led to both parties negotiating a peace treaty and ending a six-year war.

<span class="mw-page-title-main">Kingdom of Cilicia (ancient)</span> Independent state (612 BC–549 BC)

The Kingdom of Cilicia was an independent state that existed from 612 BC to 549 BC. The state was governed by the Syennesis dynasty, possibly from Greeks that moved into Cilicia towards the end of the Bronze Age. Prior to and after the independent kingdom, the Syennesis dynasty ruled Cilicia as autonomous state under the Neo-Assyrian Empire and the Achaemenid Empire.

<span class="mw-page-title-main">Persian Revolt</span> Campaign led by Cyrus the Great in ancient Persis against the Median Empire

The Persian Revolt was a campaign led by the Persian king Cyrus the Great in which Persis, which had been under Median rule, revolted against the Median kingdom and declared its independence. After several battles, the Persians defeated the Medes, establishing the Achaemenid Empire.

Solar observation is the scientific endeavor of studying the Sun and its behavior and relation to the Earth and the remainder of the Solar System. Deliberate solar observation began thousands of years ago. That initial era of direct observation gave way to telescopes in the 1600s followed by satellites in the twentieth century.

Patricia F. O'Grady is an Australian historian of philosophy specializing in ancient Greek philosophy and in particular on Thales of Miletus. She earned a doctorate in 1998 at Flinders University, with the dissertation Thales: Some Problems in Early Greek Science and Philosophy.

Labinetus or Labynetus is a name that probably refers to the kings of the Chaldean dynasty in general. The Hellenized form of the name occurs only in Herodotus' Histories.

References

  1. This date is based on the proleptic Julian calendar, which does not include a "year zero"; astronomically the year is -584.
  2. 1 2 "Eclipse path map from NASA". NASA. Archived from the original on 18 January 2006.
  3. Martin, Thomas-Henri (1864). "Sur quelques prédictions d'éclipses mentionnées par des auteurs anciens". Revue Archéologique. ix: 170–199. JSTOR   41734368.
  4. 1 2 Neugebauer, Otto (1969). The Exact Sciences in Antiquity. Dover Publications. p. 142. ISBN   978-0-4862-2332-2.
  5. 1 2 Querejeta, M. (2011). "On the Eclipse of Thales, Cycles and Probabilities". Culture and Cosmos. 15: 5–. arXiv: 1307.2095 . Bibcode:2013arXiv1307.2095Q. doi:10.46472/CC.0115.0203.
  6. 1 2 3 4 Panchenko, D. (2004). "Thales's Prediction of a Solar Eclipse". Journal for the History of Astronomy. 25 (4): 275–. Bibcode:1994JHA....25..275P. doi:10.1177/002182869402500402. S2CID   118329282.
  7. Stephenson, F. Richard; Fatoohi, Louay J. (1997). "Thales's Prediction of a Solar Eclipse". Journal for the History of Astronomy. 28 (4): 279. Bibcode:1997JHA....28..279S. doi:10.1177/002182869702800401. S2CID   118345852.
  8. "Happy Birthday to Science", by Tom Mandel, at the Chicago Sun-Times (archived at HighBeam Research); published 28 May 1990; retrieved 11 April 2014
  9. The Histories . Herodotus.
  10. Cicero: De divinatione 1,49 (online)
  11. Pliny the Elder: Naturalis historia 2,9 (53) (online)
  12. Westfall, John; Sheehan, William (2014). Celestial Shadows: Eclipses, Transits, and Occultations. Springer. p. 109. ISBN   978-1-4939-1535-4.
  13. Frost, Natasha (8 August 2017). "Was the First Eclipse Prediction an Act of Genius, a Brilliant Mistake, or Dumb Luck?". Atlas Obscura. Retrieved 5 August 2019.