Meton of Athens facts for kids

Meton of Athens (Greek: Μέτων ὁ Ἀθηναῖος) was a smart Greek mathematician, astronomer, geometer, and engineer. He lived in Athens way back in the 5th century BC. Meton is best known for his calculations about a special 19-year calendar pattern. This pattern is even named after him: the Metonic cycle. He introduced it in 432 BC for the lunisolar Attic calendar used in Athens.

The Metonic Cycle: A Clever Calendar Trick

The Metonic calendar uses a cool idea. It noticed that 19 solar years (how long it takes Earth to go around the sun) are almost the same length as 235 lunar months (how long it takes the moon to go through all its phases). This means that a certain day of a lunar month will often happen on the same day of the solar year as it did 19 years before!

Meton worked with another person named Euctemon to make these observations. We don't know much else about Euctemon.

Improving the Calendar: The Callippic Cycle

Later, another Greek astronomer named Callippus built on Meton's work. He suggested something called the Callippic cycle. A Callippic cycle lasts for 76 years, which is exactly four Metonic cycles. Callippus made the lunisolar calendar even better. He took away one day from the fourth Metonic cycle in each Callippic cycle. This helped the calendar stay perfectly lined up with the seasons of the solar year.

Ancient Calculators: The Antikythera Mechanism

The oldest known astronomical calculator in the world is the Antikythera mechanism. It was made around the 2nd century BC. This amazing device could perform calculations based on both the Metonic and Callippic calendar cycles. It even had separate dials for each!

Meton's Observatory

You can still see the foundations of Meton's observatory in Athens today. They are located right behind the podium of the Pnyx, which was the ancient parliament building. Meton used his observatory to find the exact dates of the equinoxes and solstices. These are special days when the sun is directly over the equator (equinoxes) or at its highest or lowest point in the sky (solstices).

He did this by watching the sunrise from his observatory. During the summer solstice, the sun rose in line with a local hill called Mount Lycabetus. Six months later, during the winter solstice, the sun rose over Mount Hymettos in the southeast. This means that from Meton's observatory, the sun seemed to move along a 60-degree arc between these two points on the horizon every six months. The middle line of this arc pointed directly towards the Acropolis.

These natural landmarks were very important. The summer solstice was the day the Athenians used to start their calendar year. The first month of their new year, Hekatombaion, began with the first new moon after the summer solstice.

Meton in Pop Culture

Meton even appears briefly as a character in a play! He is in Aristophanes' play The Birds, which was written in 414 BC. In the play, he comes on stage carrying surveying tools and is described as a geometer.

What We Know About Meton

Most of what we know about Meton comes from ancient historians. For example, Ptolemy wrote that a stone tablet, called a stela, was set up in Athens. This tablet had a record of Meton's observations and explained the Metonic cycle. Sadly, none of Meton's own writings or works have survived to this day.

See also

In Spanish: Metón para niños