How to read the atlas
Time runs left → right (700 → 1600 CE, linear, with 50-year ticks and bold century lines). Vertical rows are centres of astronomical work — the House of Wisdom, the eastern Iranian courts, Fatimid Cairo, al-Andalus, Marāgha, Damascus, Samarkand, Istanbul — plus a top row for the inheritance the tradition began from and a bottom row for the political and dynastic events that shaped it. Each glyph sits at its event's date on its centre's row. Bars are people: a horizontal bar shows the years an astronomer was actively working, with a small cameo at its left edge.
The dashed vermilion line at 1258 marks the Mongol sack of Baghdad — the single sharpest rupture on the page. It did not end the tradition: Marāgha, then Samarkand, then Istanbul all came after it. Dates are given in the Common Era on the axis; each deep-dive card also gives the approximate Hijri year (AH), since that is the calendar the astronomers themselves kept.
Glyph shape is the kind of contribution: filled circle = observation or discovery, open circle = treatise or star catalogue, square = founding of an institution, triangle = instrument or technique, diamond = political or dynastic event. Glyph fill colour matches the centre's stripe.
The centres, briefly
Two threads that make this more than a list
The first is the zīj — the astronomical handbook of tables. It is the connective tissue of the whole tradition: al-Fazārī's Zīj al-Sindhind in Baghdad feeds al-Battānī's Ṣābiʾ Zīj, which feeds al-Zarqālī's Toledan Tables, which feed al-Ṭūsī's Zīj-i Īlkhānī, which is answered by Ulugh Beg's Zīj-i Sulṭānī. Each generation re-observed rather than merely copying, and each catalogue is a fresh measurement of the same sky.
The second is the critique of Ptolemy. Ibn al-Haytham's al-Shukūk ʿalā Baṭlamyūs ("Doubts on Ptolemy") named the physical incoherence of the equant; the Marāgha astronomers — al-Ṭūsī with his "couple," al-ʿUrḍī with his lemma — built geometric devices to remove it; and Ibn al-Shāṭir in Damascus produced fully non-Ptolemaic planetary models whose lunar theory is mathematically identical to the one Copernicus would publish in 1543. Whether that identity reflects transmission or independent rediscovery is still debated; the models themselves are on this atlas, and the reader can judge.
The sky still speaks Arabic
More than two hundred of the star names in current use are Arabic, most of them transmitted through ʿAbd al-Raḥmān al-Ṣūfī's Book of the Fixed Stars (964) and the Latin translations that followed: Aldebaran (الدَّبَران, "the follower"), Altair (الطائر, "the flyer"), Betelgeuse (يد الجوزاء), Rigel (رِجل, "foot"), Vega (from النسر الواقع, "the swooping eagle"), Deneb (ذنب, "tail"), Fomalhaut, Algol, and Achernar among them. Al-Ṣūfī also recorded, as "a little cloud," the object we now call the Andromeda Galaxy — the earliest known notice of a galaxy beyond our own.
Methodology — what counts, what does not
Inclusion. An entry qualifies if (a) the work was done within the Islamic scholarly world between roughly 700 and 1600 CE — under any dynasty, by scholars of any confessional background working in Arabic or Persian — and (b) the result was a primary contribution to astronomy or its instrumentation, mathematical astronomy, or an observatory's institutional infrastructure. The tradition was not confessionally uniform: Ṣābian-descended (al-Battānī), Jewish, and Christian astronomers worked inside it, and the atlas credits the work, not a faith.
Exclusion. Astrology as prognostication is not catalogued as astronomy, though the historical entanglement of the two (and the courtly patronage it brought) is noted where it bears on the observational work. Pure mathematics with no astronomical application, and the vast medical, philosophical, and geographical output of the same figures (Ibn Sīnā's medicine, al-Bīrūnī's ethnography), are outside scope except where they touch the sky directly.
Primary sources. Every deep-dive card cites a primary source — a zīj, a treatise, an instrument text, or a securely dated modern critical edition — with a stable link where a digitized manuscript or edition exists. Transliteration follows a light IJMES-style scheme; regnal and death dates follow the standard reference literature (Kennedy's Survey of Islamic Astronomical Tables, King, Saliba, Ragep). Where a date or attribution is genuinely contested, the card says so rather than choosing for the reader.
On "decline." This atlas ends near 1600 with Taqī al-Dīn not because astronomy in the Islamic world stopped — it did not; observatories, timekeeping, and instrument-making continued for centuries — but because the coherent institutional thread this volume traces reaches a natural close there, and the story then branches into Ottoman, Safavid, and Mughal chapters that deserve their own volumes.
Companion RAVEN material
Al-Ṣūfī's Book of the Fixed Stars sits at the head of the star-nomenclature lineage that every catalogue in the RAVEN Catalogs still inherits — the Arabic proper names on modern charts are his. The Marāgha and Samarkand instrument programs (the mural sextant, the armillary sphere, the Fakhrī sextant) are historical anchors for the ground-based instrumentation traced in the RAVEN Platforms Atlas. Ibn al-Haytham's Book of Optics and al-Fārisī's raindrop theory of the rainbow are upstream of the optics in the RAVEN Foundations series. And this volume is designed to read directly into Volume I — Astronomy by Jesuit Hands: the Toledo translations at the left edge of the European Renaissance are the hand-off between the two.