Meton of Athens ( el, Μέτων ὁ Ἀθηναῖος; ''gen''.: Μέτωνος) was a

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

mathematician A mathematician is someone who uses an extensive knowledge of mathematics in their work, typically to solve mathematical problems. Mathematicians are concerned with numbers, data, quantity, structure, space, models, and change. History On ...

astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, moons, comets and galaxies – in either ...

geometer A geometer is a mathematician whose area of study is geometry. Some notable geometers and their main fields of work, chronologically listed, are: 1000 BCE to 1 BCE * Baudhayana (fl. c. 800 BC) – Euclidean geometry, geometric algebra * ...

, and

engineer Engineers, as practitioners of engineering, are professionals who invent, design, analyze, build and test machines, complex systems, structures, gadgets and materials to fulfill functional objectives and requirements while considering the limit ...

who lived in

Athens Athens ( ; el, Αθήνα, Athína ; grc, Ἀθῆναι, Athênai (pl.) ) is both the capital and largest city of Greece. With a population close to four million, it is also the seventh largest city in the European Union. Athens dominates ...

in the 5th century BC. He is best known for calculations involving the eponymous 19-year

Metonic cycle The Metonic cycle or enneadecaeteris (from grc, ἐννεακαιδεκαετηρίς, from ἐννεακαίδεκα, "nineteen") is a period of almost exactly 19 years after which the lunar phases recur at the same time of the year. The rec ...

, which he introduced in 432 BC into the

lunisolar A lunisolar calendar is a calendar in many cultures, combining lunar calendars and solar calendars. The date of Lunisolar calendars therefore indicates both the Moon phase and the time of the solar year, that is the position of the Sun in the E ...

Attic calendar The Attic calendar or Athenian calendar is the lunisolar calendar beginning in midsummer with the lunar month of Hekatombaion, in use in ancient Attica, the ancestral territory of the Athenian polis. It is sometimes called the Greek calendar be ...

. Euphronios says that Colonus was Meton's

deme In Ancient Greece, a deme or ( grc, δῆμος, plural: demoi, δημοι) was a suburb or a subdivision of Athens and other city-states. Demes as simple subdivisions of land in the countryside seem to have existed in the 6th century BC and ear ...

Work

The

Metonic calendar The Metonic cycle or enneadecaeteris (from grc, ἐννεακαιδεκαετηρίς, from ἐννεακαίδεκα, "nineteen") is a period of almost exactly 19 years after which the lunar phases recur at the same time of the year. The recu ...

incorporates knowledge that 19

solar year A tropical year or solar year (or tropical period) is the time that the Sun takes to return to the same position in the sky of a celestial body of the Solar System such as the Earth, completing a full cycle of seasons; for example, the time f ...

s and 235

lunar month In lunar calendars, a lunar month is the time between two successive syzygies of the same type: new moons or full moons. The precise definition varies, especially for the beginning of the month. Variations In Shona, Middle Eastern, and Eur ...

s are very nearly of the same duration. Consequently, a given day of a lunar month will often occur on the same day of the solar year as it did 19 years previously. Meton's observations were made in collaboration with

Euctemon Euctemon ( el, Εὐκτήμων, ''gen.'' Εὐκτήμωνος; fl. 432 BC) was an Athenian astronomer. He was a contemporary of Meton and worked closely with this astronomer. Little is known of his work apart from his partnership with Meton and ...

, about whom nothing else is known. The Greek astronomer

Callippus Callippus (; grc, Κάλλιππος; c. 370 BC – c. 300 BC) was a Greek astronomer and mathematician. Biography Callippus was born at Cyzicus, and studied under Eudoxus of Cnidus at the Academy of Plato. He also worked with Aristotle at th ...

expanded on the work of Meton, proposing what is now called the Callippic cycle. A Callippic cycle runs for 76 years, or four Metonic cycles. Callippus refined the lunisolar calendar, deducting one day from the fourth Metonic cycle in each Callippic cycle (i.e., after 940 synodic lunar periods had elapsed), so as to better keep the lunisolar calendar synchronized with the seasons of the solar year. The world's oldest known astronomical calculator, the

Antikythera Mechanism The Antikythera mechanism ( ) is an Ancient Greek hand-powered orrery, described as the oldest example of an analogue computer used to predict astronomical positions and eclipses decades in advance. It could also be used to track the four-yea ...

(2nd century BC), performs calculations based on both the Metonic and Callipic calendar cycles, with separate dials for each. The foundations of Meton's observatory in Athens are still visible just behind the podium of the

Pnyx The Pnyx (; grc, Πνύξ ; ell, Πνύκα, ''Pnyka'') is a hill in central Athens, the capital of Greece. Beginning as early as 507 BC ( Fifth-century Athens), the Athenians gathered on the Pnyx to host their popular assemblies, thus making ...

, the ancient parliament. Meton found the dates of equinoxes and solstices by observing sunrise from his observatory. From that point of observation, during the summer solstice, sunrise was in line with the local hill of Mount Lycabetus, while six months later, during the winter solstice, sunrise occurs over the high brow of Mount Hymettos in the southeast. So from Meton's observatory the Sun appears to move along a 60° arc between these two points on the horizon every six months. The bisector of the observatory's solstitial arc lies in line with the Acropolis. These topological features are important because the summer solstice was the point in time from which the Athenians measured the start of their calendar years. The first month of the new year, Hekatombaion, began with the first new moon after the summer solstice.Hannah, R. 'Greek and Roman Calendars'. London: Duckworth, pages 52-55. Meton appears briefly as a character in

Aristophanes Aristophanes (; grc, Ἀριστοφάνης, ; c. 446 – c. 386 BC), son of Philippus, of the deme Kydathenaion ( la, Cydathenaeum), was a comic playwright or comedy-writer of ancient Athens and a poet of Old Attic Comedy. Eleven of his for ...

' play '' The Birds'' (414 BC). He comes on stage carrying surveying instruments and is described as a

. What little is known about Meton is related by ancient historians. According to

Ptolemy Claudius Ptolemy (; grc-gre, Πτολεμαῖος, ; la, Claudius Ptolemaeus; AD) was a mathematician, astronomer, astrologer, geographer, and music theorist, who wrote about a dozen scientific treatises, three of which were of importance ...

, a

stela A stele ( ),Anglicized plural steles ( ); Greek plural stelai ( ), from Greek , ''stēlē''. The Greek plural is written , ''stēlai'', but this is only rarely encountered in English. or occasionally stela (plural ''stelas'' or ''stelæ''), wh ...

or table erected in Athens contained a record of Meton's observations, and a description of the Metonic cycle.Smith, W. ''Dictionary of Greek and Roman Biology and Mythology''. Little and Brown, 1867, p. 1069 None of Meton's works survive.

Notes

References

* Toomer, G. J. "Meton." ''Dictionary of Scientific Biography'' 9:337–40. * Pannekoek, A. "Planetary Theories – the Planetary Theory of Kidinnu." ''Popular Astronomy'' 55, 10/1947, p 422

External links

Meton of Athens

{{DEFAULTSORT:Meton of Athens 5th-century BC Athenians Ancient Greek astronomers Ancient Greek engineers Ancient Greek mathematicians 5th-century BC mathematicians