Babylonian astronomical diaries

The Babylonian astronomical diaries are old writings made by people in Babylon. These writings are on clay tablets and use a special way of writing called cuneiform. They were written in a language called Akkadian language.

The diaries have careful notes about what they saw in the sky, like the movement of the moon and stars.

Besides sky watching, the diaries also tell us about important events in the kingdom, the weather, and even how much things cost. They kept records of prices for six items: barley, dates, mustard (cuscuta), cress (cardamom), sesame, and wool, on specific dates.

Today, most of these precious clay tablets are kept safe in the British Museum. Experts believe these diaries were used to help write other important histories called the Babylonian Chronicles. They are a valuable way for us to learn about life and science a very long time ago.

History

The Babylonians were the first to notice that events in the sky happen in patterns. They used math to predict these events. The oldest important book about stars is called the Venus tablet of Ammisaduqa. It shows when Venus could be seen in the sky over 21 years. This proves that they knew planets move in regular ways.

They started keeping careful records of what they saw in the sky during the time of Nabonassar (747–734 BC). These records helped them find patterns, like the 18-year cycle of lunar eclipses called the Saros cycle.

Structure

Most of the clay tablets we have are broken, but we can often tell when they were written by looking at the stars they mention. They cover many years, mostly between 400 and 60 BCE.

Each diary usually talks about four to six months at a time, split into monthly parts. Most of each month’s entry is about what the stars and planets did each day. At the end of the month, they note how high the Euphrates river was, the prices of goods like food and wool in Babylon, and sometimes big events like wars or visits from important people.

We don’t know exactly why they kept these diaries, but they seem related to trying to predict the future. They are very important for learning about the history and economy of Babylon during ancient times, especially from the Late Achaemenid to the Hellenistic Babylonia periods.

Notable entries

Here are some interesting events recorded in the Babylonian astronomical diaries.

• Antiochus, son of Seleucus IV faced trouble in 170 BC.
• The king of the world, Alexander, sent his scouts to the people of Babylon before entering the city.
• There is a description of the appearance of Halley's Comet, translated by Hermann Hunger.

Translation

Translations of the Diaries are in a set of books called Astronomical Diaries and Related Texts from Babylonia. These books were edited by Abraham Sachs and Hermann Hunger. The books include:

• Volume I – Diaries from 652 B.C. to 262 B.C. (ISBN 3-7001-1227-0, 1988).
• Volume II – Diaries from 261 B.C. to 165 B.C. (ISBN 3-7001-1705-1, 1989).
• Volume III – Diaries from 164 B.C. to 61 B.C. (ISBN 3-7001-2578-X, 1996).
• Volume IV – Undated Diaries and Addenda (ISBN 978-3-7001-9032-5, 2022).
• Volume V – Lunar and Planetary Texts (ISBN 3-7001-3028-7, 2001), with information about the moon and planets from the 8th century BC to the 1st century BC.
• Volume VI – Goal Year Texts (ISBN 978-3-7001-3727-6, 2006), with more information about the moon and planets, from the 3rd century BC to the 1st century BC.
• Volume VII – Almanacs and Normal Star Almanacs (ISBN 978-3-7001-7627-5, 2014), with astronomical guides, from the 3rd century BC to the 1st century AD.