Euctemon was an Athenian

Athens

Athens , is the capital and largest city of Greece. Athens dominates the Attica region and is one of the world's oldest cities, as its recorded history spans around 3,400 years. Classical Athens was a powerful city-state...

 astronomer

Astronomer

An astronomer is a scientist who studies celestial bodies such as planets, stars and galaxies.Historically, astronomy was more concerned with the classification and description of phenomena in the sky, while astrophysics attempted to explain these phenomena and the differences between them using...

. 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 what is mentioned by Ptolemy

Ptolemy

Claudius Ptolemy , was a Roman citizen of Egypt who wrote in Greek. He was a mathematician, astronomer, geographer, astrologer, and poet of a single epigram in the Greek Anthology. He lived in Egypt under Roman rule, and is believed to have been born in the town of Ptolemais Hermiou in the...

. With Meton, he made a series of observations of the solstice

Solstice

A solstice is an astronomical event that happens twice each year when the Sun's apparent position in the sky, as viewed from Earth, reaches its northernmost or southernmost extremes...

s (the points at which the sun is at greatest distance from the equator) in order to determine the length of the tropical year. Geminus

Geminus

Geminus of Rhodes , was a Greek astronomer and mathematician, who flourished in the 1st century BC. An astronomy work of his, the Introduction to the Phenomena, still survives; it was intended as an introductory astronomy book for students. He also wrote a work on mathematics, of which only...

 and Ptolemy quote him as a source on the rising and setting of the stars. The lunar crater Euctemon

Euctemon (crater)

Euctemon is a lunar crater that is located in the northern part of the Moon, along the northwest rim of the crater Baillaud. To the southwest of Euctemon is the large walled plain Meton, and to the north-northeast lies the crater De Sitter...

is named after him.

External links

• Imago Mundi: Euctemon
• The Ancient Library
• Greek Astronomy