Mystery of a 2,500 year old verse solved by astronomy! Physicists date 'Midnight Poem' to 570 BC using simulation of night sky

From the discovery of seven of the planets to Pythagoras' theorem, modern astronomy has a lot to be thankful to ancient Greece for.

Now in a rare case of role reversal, modern astronomy has helped to shed light on ancient Greece.

Astronomers used an advanced simulation of the solar system to date an ancient love poem, by working out exactly where a certain cluster of stars would appear in the sky 2,5000 years ago.

The Pleiades (pictured) also known as Seven Sisters, is an open star cluster containing middle-aged hot B-type stars located in the constellation of Taurus. Physicists from the University of Texas used advanced astronomical software to accurately date lyric poet Sappho's 'Midnight Poem,' which describes the Pleiades

Physicists and astronomers from the University of Texas used advanced astronomical software to accurately date lyric poet Sappho's 'Midnight Poem,' which describes the night sky over Greece.

Sappho was a Greek lyric poet, who was born between 630 and 612 BC on the island of Lesbos, and died around 570 BC. She was a leading female poet of her time and closely rivaled Homer.

One of her most famous poems is called 'Midnight Poem', thought to be written in a letter to a love interest. 

The poem has puzzled historians because it contains clues about when it could have been written, but the exact date was not known until now.

The poem mentions a star cluster known as the Pleiades having set at around midnight, when observed by from the Greek island of Lesbos. 

The Pleiades, also known as Seven Sisters, is an open star cluster containing middle-aged hot B-type stars located in the constellation of Taurus.

The researchers used software called Starry Night version 7.3 to identify the earliest date the Pleiades would have set at midnight or earlier in local time.

They found 25 January in 570 BC would be the earliest date the poem could relate to. 

Sappho was a Greek lyric poet, who was born between 630 and 612 BC on the island of Lesbos, and died around 570 BC. Detail from a Pompeii fresco painting of Sappho pictured. Astronomers say the poet should be considered an informal contributor to early Greek astronomy as well as to Greek society at large

'This is an example of where the scientific community can make a contribution to knowledge described in important ancient texts, ' said Professor Manfred Cuntz, lead author of the study. 

'Estimations had been made for the timing of this poem in the past, but we were able to scientifically confirm the season that corresponds to her specific descriptions of the night sky in the year 570 BC.'

The researchers also calculated the last date the Pleiades would have been seen at the end of astronomical twilight - the moment when the Sun's altitude is -18 degrees and the sky is regarded as 'perfectly dark' - was 31 March that year.

'The timing question is complex as at that time they did not have accurate mechanical clocks as we do, only perhaps water clocks' said Professor Cuntz. 

'For that reason, we also identified the latest date on which the Pleiades would have been visible to Sappho from that location on different dates some time during the evening.'

The planetarium software meant the researchers could create the night sky of ancient Greece for Sappho's place and time.

An image of the Pleiades in infrared, showing the associated dust, taken by Nasa's Spitzer space telescope. Pleiades is among the nearest star clusters to Earth and is the cluster most obvious to the naked eye in the night sky

A painting of Sappho on an Attic Red-Figure 'kalathos' vase was made by the 'Brygos Painter‘ in about 470 BC. This pot is now in the Staatliche Antikensammlungen in Munich

'Use of planetarium software permits us to simulate the night sky more accurately on any date, past or future, at any location,' said Levent Gurdemir, co-author and director of the planetarium.  

'This is an example of how we are opening up the planetarium to research into disciplines beyond astronomy, including geosciences, biology, chemistry, art, literature, architecture, history and even medicine.'  

Sappho's interest in astronomy was not restricted to the 'Midnight Poem' - other examples of her work make references to the sun, the moon, and planet Venus.

'Sappho should be considered an informal contributor to early Greek astronomy as well as to Greek society at large,' Professor Cuntz added. 

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

'This research helps to break down the traditional silos between science and the liberal arts, by using high-precision technology to accurately date ancient poetry,' said Morteza Khaledi, dean of UTA's College of Science. 

'It also demonstrates that the planetarium's reach can go way beyond astronomy into multiple fields of research.'