Rise of the Pleiades dates ancient Greek poem

Modern software recreated the night sky more than 2,500 years ago to confirm the timing of a famous Greek poem.

A trio of astronomers, led by the University of Texas at Arlington’s Manfred Cuntz, took a section from Greek lyric poet Sappho’s Midnight Poem and recreated constellations of the time. Based on the rise of a star cluster, the Pleiades, they calculated the poem was set 2,586 years ago between 25 January and 31 March 570 BCE.

Sappho was born and died on the Greek island Lesbos. Even though she was a prolific poet – rivalling Homer, according to the researchers – little remains of her work. Only around 200 fragments survive today.

Midnight Poem is one such piece. A section mentions the narrator, all alone, watching the Pleiades setting before midnight:

The moon has set,
and the Pleiades;
it is midnight,
the time is going by,
And I sleep alone.

The Pleiades, a distinctive group of bright stars also known as the Seven Sisters, is visible from the northern hemisphere and most of the southern. The cluster featured in many ancient cultures, including those of the Australian Aborigines, Vikings, Mayans and Babylonians.

Sappho wasn’t a stranger to cosmological landmarks in her poetry. But her specific mention of the Pleiades, Cuntz and colleagues realised, provided a handy point for the time of year Midnight Poem was set.

In 1990, computer scientists Israel Herschberg and Johan Mebius studied the language of the poem and concluded it was penned somewhere in late winter or early spring.

So Cuntz and colleagues set out to confirm or refute this by recreating the night sky in the year of Sappho’s death – 570 BCE – as seen from Lesbos.

They saw the Pleiades set at midnight on 25 January. And as the year progressed, the star cluster set earlier until 31 March, the last date it could have been visible in a dark sky. This confirmed Herschberg and Mebius’ approximation.

The researchers admit choosing the year 570 BCE was an arbitrary decision. But the Pleiades’ movement across the sky changed very little year to year for someone watching from Lesbos. Similar dates could be found 40 years either side.

For her stellar observations, “Sappho should be considered an informal contributor to early Greek astronomy as well as to Greek society at large”, Cuntz says.

“Not many ancient poets comment on astronomical observations as clearly as she does.”

The work was published in the Journal of Astronomical History and Heritage.