How to read the atlas
Time runs left → right from 1800 BCE to 100 CE on a linear axis. Rows are cities, courts, temples, and transmission settings. Thick horizontal strips show the useful life of a tablet corpus or scholarly institution; wedge-shaped glyphs are dated records, compilations, observations, methods, or acts of transmission. A thin dashed range around a glyph means its date is reconstructed or approximate.
The modern split between astronomy and astrology does not map cleanly onto Mesopotamian scholarship. Celestial omens, observation reports, calendars, mathematical prediction, and royal decision-making belonged to overlapping learned practices. This volume therefore shows the transformation without pretending that omen scholarship simply “became” modern astronomy.
The institutional rows
Four transformations across the record
From event to series. A single unusual sky event became useful when it was copied into a named tablet series and compared with earlier cases. Enūma Anu Enlil and the Assyrian reports preserve this serial logic.
From series to diary. By the first millennium BCE, observers in Babylon were recording lunar and planetary phenomena, weather, river levels, prices, and political events month after month. The Astronomical Diaries turned the sky into a continuous institutional archive.
From diary to prediction. Goal-Year Texts, almanacs, period relations, and the System A and B ephemerides converted accumulated observations into reusable procedures. Prediction could now be calculated for dates that had not yet occurred.
From Mesopotamia outward. Zodiacal coordinates, period relations, and observation records passed into Greek astronomy and later traditions. The exact paths are unevenly documented; the transmission is real, but simple stories of one named inventor handing a finished system to another culture are not.
Methodology — what counts, what does not
Inclusion. Entries require a cuneiform witness, a recoverable ancient testimony, or a well-defined scholarly reconstruction that materially changes the history of observation or mathematical astronomy.
Dates. The date of a surviving copy is not silently substituted for the date of the observations or compilation it preserves. Where these differ—as with the Venus Tablet—the card states both and displays an uncertainty range.
Authorship. Named attributions such as Nabû-rīmanni or Kidinnu are retained only as historiographic claims and flagged when the evidence is late or disputed. Anonymous scribal labor remains anonymous.
Language. Cuneiform signs are used as material labels, not as decorative pseudo-translations. 𒀯 is the sign conventionally transliterated MUL, “star”; 𒀳 is APIN, “plough.”
Sources. Object records link to the British Museum or CDLI; text corpora link to ORACC where available. Interpretive claims rely on critical editions and specialist histories listed below.
Companion RAVEN material
The numerical and observational inheritance continues into Volume III — Astronomy in India, Volume II — Astronomy in the Islamic World, and the future Greek and Hellenistic volume. The surviving tablets are ancient predecessors of the persistent archives mapped in the Archives Atlas: stored observations becoming more valuable as their time baseline grows.