Ars Astronomica – English translations of rare Hebrew and Latin astronomy texts

Jul 28, 2026 12:25 PM - 5 hours ago 87

A scholarly imprint producing first English translations of humanities Hebrew and Latin useful successful astronomy, cosmology, and earthy philosophy.

These texts span centuries, and astir person ne'er appeared successful English. One – Gersonides’ 136-chapter mathematical astronomy – was ne'er printed and survives only successful manuscript. They mention and reply 1 another, addressing the aforesaid cosmological questions, yet until now nary 1 could publication them broadside by broadside successful a azygous language.

The corpus

Date Author Work Source Description Translator Version

1665	Athanasius Kircher	Mundus Subterraneus footnotes	Internet Archive — athanasiikircher12kirc	A immense effort to explicate the full hidden world beneath our feet.	2
c. 1613	David Gans	Nechmad ve-Na’im footnotes	National Library of Israel — Rosetta IE32709375, shelfmark 35 V 1770 (catalog NNL_ALEPH990011964030205171).	A Hebrew textbook of astronomy that presents the Ptolemaic exemplary of the heavens for a Hebrew-reading audience, weaving the cutting-edge European subject of its time together pinch the medieval Jewish cosmological contented — its writer having personally visited the Danish astronomer Tycho Brahe.	2
1592 (first composed/printed Prague, שנ”ב; this is simply a later reprint)	David Gans	Tzemach David footnotes	National Library of Israel — Rosetta IE90688593 (record branded “Vol.1-3”).	A Hebrew humanities chronicle successful 2 parts by David Gans: the first traces Jewish history from creation to the sixteenth period — biblical figures, sages, and rabbis; the 2nd surveys world and gentile history from Julius Caesar to Emperor Rudolph.	2
1665	Giovanni Battista Riccioli	Astronomia Reformata footnotes	e-rara ETH-Bibliothek Zürich — title-info 141744	A mature reckoning pinch the heavens arsenic the scope was revealing them — a sequel to the immense Almagestum Novum (1651), built connected further years of study astatine Bologna pinch the collaborator Grimaldi, pinch caller measurements and corrected parameters astatine halfway stage.	2
c. 1123 (composition; this is simply a later manuscript copy)	Jacob ben Samson (attrib.)	Perush Sod ha-Ibbur footnotes	OPenn UPenn-hosted digitization of the British Library manuscript — British Library Add MS 11639, ff. 511r–545v	An early Ashkenazi commentary connected the “secret of the calendar” (sod ha-ibbur) — the computation of the Hebrew calendar: the molad (lunar conjunction), the tequfot (seasonal points), the nineteen-year intercalation cycle, and the rules governing leap years and show dates.	2
1629	Joseph Solomon Delmedigo	Sefer Elim footnotes	Internet Archive — seferelim00delmuoft	A wide-ranging Hebrew technological compendium, framed arsenic a reply to questions put by the Karaite clever clever Zerah ben Nathan.	2
1640	Longomontanus	Astronomia Danica footnotes	Internet Archive — astronomiadanica00long	A broad textbook of astronomy and the definitive method relationship of the Tychonic strategy — Earth astatine rest, the Sun circling it, the planets circling the Sun.	2
1654	Pierre Gassendi	Tychonis Brahei Vita footnotes	Internet Archive — den-kbd-pil-130018157889-001	A life of the Danish astronomer Tycho Brahe (1546–1601): his fabled observatory connected the land of Hven, the magnificent instruments he built, the campaigns of study that remade astronomy, his bold exemplary of the cosmos, and his turbulent last years successful Prague.	2
c. 1136	R. Avraham barroom Ḥiyya ha-Nasi	Cheshbon Mahalechot ha-Kochavim footnotes	HebrewBooks.org — ID 22072	A medieval Hebrew treatise connected mathematical astronomy and the computation of the Jewish calendar.	2
c. 1122	R. Avraham barroom Ḥiyya ha-Nasi	Sefer HaIbbur footnotes	HebrewBooks.org — ID 21292	The earliest systematic Hebrew treatise connected the subject of the calendar, written successful early-twelfth-century Barcelona.	2
c. 1132	R. Avraham barroom Ḥiyya ha-Nasi	Sefer Tsurat ha-Arets footnotes	NYPL Digital Collections Dorot Jewish Division — point ce668260-c766-0132-045a-58d385a7b928	A foundational activity of medieval cosmology that lays retired the style of the cosmos arsenic the Greeks and their Arabic heirs understood it: a spherical world astatine the halfway of nested celestial spheres, the paths of sun and moon, and the zones and surface science of the inhabited world.	2
c. 1148	R. Avraham ibn Ezra	Keli ha-Nechoshet footnotes	HebrewBooks.org — ID 20850	The earliest surviving Hebrew treatise connected the astrolabe, composed successful the mid-twelfth century.	2
c. 1500	R. Eliyahu Mizrahi	Kitsur ha-Melakhat ha-Mispar footnotes	NYPL Digital Collections Dorot Jewish Division — point ce668260-c766-0132-045a-58d385a7b928	Kitsur ha-Melakhat ha-Mispar (“Compendium of the Art of Number”) is simply a Hebrew arithmetic textbook by Rabbi Eliyahu Mizrahi (ca. 1455–1526), the main rabbi of the Ottoman Empire and 1 of the foremost Jewish mathematicians of his age.	2
c. 1365	R. Immanuel Bonfils	Shesh Kenafayim footnotes	University of Pennsylvania — Kislak Center, LJS 204 Digital Scriptorium DS129	One of the astir wide copied Hebrew astronomical handbooks of the precocious Middle Ages, composed astir 1365 successful Provence.	2
late 14th c. (composition; this is simply a later manuscript copy)	R. Isaac ibn al-Aḥdab	Keli Ḥemda footnotes	Gallica / BnF — Hébreu 1031, ff. 208r–215v	Isaac ibn al-Aḥdab’s Keli Ḥemda (“The Precious Instrument”) — a explanation of the building and usage of an equatorium, an instrumentality for computing planetary positions geometrically.	2
c. 1396 (composed successful Syracuse, Sicily; this is simply a later manuscript copy)	R. Isaac ibn al-Aḥdab	Orah Selulah footnotes	Gallica / BnF — Hébreu 1086	A group of astronomical tables by Isaac ibn al-Ahdab (Sicily, precocious 14th c.) for computing the existent conjunctions and oppositions of the Sun and Moon — the Orah Selulah (“Paved Way”), 1 of the astir wide copied Hebrew astronomical table-works (surviving successful ~25 manuscripts).	2
c. 1288 (composition; this is simply a later manuscript copy)	R. Jacob ben Machir ibn Tibbon	Roba’ Yisrael footnotes	Gallica / BnF — Hébreu 1031, ff. 131r–147v	Jacob ben Machir ibn Tibbon’s treatise connected the quadrans novus — the improved astronomical quadrant of his ain invention — describing really the instrumentality is constructed and utilized for astronomical and time-keeping measurements.	2
c. 1329	R. Levi ben Gershom	Milchamot HaShem footnotes	Internet Archive — sefermilamothash00leviuoft	The Wars of the Lord is the philosophical and theological masterwork of Levi ben Gershom (Gersonides, 1288–1344), 1 of the boldest minds of medieval Provence.	2
c. 1328	R. Levi ben Gershom	Sefer HaTechunah footnotes	Gallica / BnF — MS Hébreu 724, ff. 1r–257v	A complete medieval strategy of mathematical astronomy, formally Book V, Part 1 of the Wars of the Lord.	2
15th c. (composition; this is simply a later manuscript copy)	R. Mordecai Comtino	Sefer ha-Ḥeshbon ve-ha-Middot footnotes	Gallica / BnF — Hébreu 1031, ff. 26r–65r	An instructional treatise connected arithmetic and applicable geometry by Mordecai ben Eliezer Comtino (Constantinople, 15th c.), 1 of the starring Rabbanite scholars of Byzantine Jewry.	2
1797	R. Pinchas Eliyahu Hurwitz	Sefer HaBrit HaShalem footnotes	HebrewBooks.org — ID 43670	A sweeping Hebrew encyclopedia of subject and mysticism, among the astir wide publication Hebrew books of its era.	2
c. 1310	R. Yitzchak Yisraeli	Yesod Olam footnotes	Digital Bodleian — MS. Huntington 299	One of the awesome medieval Hebrew treatises connected astronomy and the subject of the Jewish calendar, composed successful Toledo successful the first half of the fourteenth century.	2
1602	Tycho Brahe	Astronomiae Instauratae Mechanica footnotes	Internet Archive — gri_tychonisbrah00brah	A sumptuously illustrated catalog of the astir meticulous astronomical instruments built earlier the telescope, gathered connected the land observatory of Hven.	2
1610	Tycho Brahe	Astronomiae Instauratae Progymnasmata footnotes	e-rara ETH-Bibliothek Zürich — Rar 4153 DOI 10.3931/e-rara-315, entity ID 84169	The fullest connection of the observational programme that transformed the subject of the heavens.	2
1588	Tycho Brahe	De Mundi Aetherei Recentioribus Phaenomenis footnotes	Internet Archive — bub_gb_2f-EqKxRN34C	When a superb comet blazed crossed Europe successful 1577, the finest instruments of the property were turned upon it, and the measurements shattered the ancient belief successful unchanging, cleanable heavens: the comet moved freely wherever coagulated crystalline spheres were expected to be.	2
1596	Tycho Brahe	Epistolarum Astronomicarum Libri footnotes	Internet Archive — tychonisbrahedan00brah	Before technological journals existed, astronomers argued, boasted, and traded discoveries by letter.	2
c. 150–850 CE	Unknown	Mishnat ha-Middot footnotes	HebrewBooks.org — ID 39044	The earliest known Hebrew treatise connected geometry — a concise applicable manual of mensuration covering the areas and perimeters of level figures, the measurement of circles and segments, and an early worth for π.	2

Updates

2026-07-05

Added 8 useful to the corpus: Milchamot HaShem (Gersonides), Sefer HaBrit HaShalem (Hurwitz), Tzemach David (Gans), Keli Ḥemda and Orah Selulah (ibn al-Aḥdab), Roba’ Yisrael (ibn Tibbon), Perush Sod ha-Ibbur (Jacob ben Samson), and Sefer ha-Ḥeshbon ve-ha-Middot (Comtino).
Cheshbon Mahalechot ha-Kochavim (bar Ḥiyya ha-Nasi) was retitled from its earlier heading, Po’al ha-Shem ve-Cheshbon Mahalechot ha-Kochavim.
Some useful now transportation improved root records – Nechmad ve-Na’im, for one, now cites the National Library of Israel’s ain digitized exemplar.

2026-06-29

All translations are now astatine version 2, regenerated pinch the corrected pipeline. Version 1 turned retired to beryllium an intermediate shape and has been superseded.
Added caller useful to the corpus – astir precocious Sefer Tsurat ha-Arets, Kitsur ha-Melakhat ha-Mispar, and Sefer Elim.
Draft editorial footnotes are now disposable for download from a footnotes nexus beneath each work’s title.

About the translations

Translations are produced pinch an automated, AI-assisted pipeline that runs each matter done a multi-stage workflow earlier last collation. For method details, spot the translator’s translation-pipeline repo.

These translations are prepublication texts – astir publication-ready, pending the diagrams and illustrations still successful progress.

The extremity is fluent, readable modern English – a matter an knowledgeable scholar tin travel without reaching for the Latin aliases Hebrew, not 1 written only for specialists. Rather than reproduce the agelong periodic sentences and deferred verbs of the originals, the translations transportation the author’s meaning, argument, and reside into earthy modern prose: wherever Tycho builds a azygous condemnation whose main verb arrives only aft 4 nested clauses, the translator breaks it into the 2 aliases 3 a modern writer would use. Fidelity comes first, though – thing is dropped, summarized, aliases invented, and negations, numbers, method terms, and the author’s ain examples and analogies are preserved exactly. Readability ne'er comes astatine the costs of changing what the root says.

Technical vocabulary stays precise and is anchored to its modern equivalents. A cardinal Latin aliases Hebrew word of creation is glossed connected its first occurrence – the original shown alongside the English rendering – and thereafter carried successful settled English. Historical names, prima names, and specialized vocabulary transportation inline identifications: Tycho’s “Lucida Vulturis volantis” is identified arsenic Altair successful Aquila; Gersonides’ medieval Hebrew astronomical terminology is mapped to the Ptolemaic strategy it describes.

Mathematical and astronomical contented – sexagesimal values, spherical triangle computations, almanac arithmetic, tabular information – is reproduced pinch the precision of the originals, compartment by compartment and grade by degree. Compositor errors successful the root are corrected inline pinch [recte: ...] notation alternatively than silently emended. Uncertain readings owed to ink damage, worn type, aliases ambiguous letterforms are marked pinch [?], preserving the translator’s champion reference while flagging it for editorial review.

Illustrations and diagrams

The publically disposable PDFs are text-only. Geometric figures, instrumentality schematics, concentric-sphere charts, and different diagrams from the root useful are extracted and replaced pinch system descriptions identifying each label, arc, point, and geometric narration visible successful the original woodcut aliases engraving. Tycho’s De Mundi Aetherei, for example, carries 93 specified figures, from spherical-astronomy constructions to the two-circle presumption of the comet’s eccentric orbit wrong the star sphere. For a high-quality illustrated people version of immoderate of these works, please get successful touch utilizing the interaction specifications below.

Support this project

Upright logic dictates that the recipients of the good, of immoderate type and level of beneficence it whitethorn be, must show gratitude and blessing to the beneficent personification successful each measurement possible, commensurate pinch the worth of the beneficence. And 1 who has benefited each the group of the world – for example, 1 who invented a caller instrumentality for the bully of the world, aliases a bully book – it is fitting for each discerning person, retired of the responsibility of emotion of chap beings, to astatine slightest acquisition it, truthful that the man will profit and his bosom will beryllium encouraged thereby to invent yet much bully instruments successful the world. And similarly, each different wise-hearted group will likewise strive and exert themselves to invent bully things and instruments needed for the repair of the world and its perfection.

And therefore, whoever says: “What do I request this caller instrumentality for?” – he does not enactment good towards the world. For if not for the man who invented it, wherever would you be? And what would your metropolis do? And much than this, if the man did not exert himself, what would the world do?

R. Pinchas Eliyahu Hurwitz, Sefer HaBrit

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Email: [email protected]
X: @ArsAstronomica

License

The original useful are successful the nationalist domain and were obtained from a assortment of sources, including digitized room collections and different unfastened archives. No declare of ownership is made complete the root texts.

All translations successful this postulation are © Scott Weisman. All authorities reserved, isolated from arsenic granted by the licence below.

The translations are made disposable nether the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International license. You are free to stock them for non-commercial purposes pinch attribution; you whitethorn not modify them aliases usage them commercially without anterior written permission.