Wednesday, March 2, 2011

When the Heavens Converted to Christianity

by Stephen J. Gertz

Engraved title page: The Christian Firmament:
The twelve apostles, formerly the twelve signs of the Zodiac

Has this ever happened to you? You go to bed, and the patterns formed by celestial bodies in the night sky are as they have been since ancient times: Orion's Orion, Capricorn's Capricorn; Ursa Minor's Ursa Minor, Cygnus is Cygnus.

But when you wake up in the morning Orion is Joseph, father of Jesus; Capricorn is St. Simon the Zealot; Ursa Minor is Solomon's Crown; and Cygnus is St. Helen, who I've never heard of aside from her role as Angry Volcano in The Washington State Story. The constellations have undergone an identity crisis; who's who, what's what? You don't recognize the fifty-four you're familiar with.

I hate when that happens. And, apparently, so, too, did people one day in 1627.

Constellation IX: St.Helen, formerly Cygnus.
At that star-crossed time, Julius Schiller (1580-1627), a lawyer - a lawyer! - and cartographer from Augsburg, Germany, published Coelum stellatum Christianum (Christian Starry Heavens), an atlas of celestial maps. Within, Schiller  replaced all of the pagan constellations named after the signs of the Zodiac and figures from Greek mythology with those from the New Testament and Christianity. The twelve zodiacal constellations, for example, were renamed for the twelve apostles - Taurus the Bull became St. Andrew, etc. Eridanus became the Red Sea; Argo became Noah's Ark; and Andromeda became the Sepulcher of Christ. A massive, forced conversion had taken place.

Constellation VII: The Three Kings, formerly Hercules.

That the heavens of God and Christ were corrupted by pagan influence was too much to bear; something had to be done.

Constellation I: St. Michael the Archangel, formerly Ursa Minor.

Schiller’s new system, however, was too radical a change and never gained acceptance and traction; the constellations had been doing just fine for two thousand years and the religious imperative was not felt by contemporary scientists - nor anyone else, for that matter. excepting the  Jesuits and highly pious members of the laity. It's similar to the failure of the metric system in the U.S.: Despite the Metric Conversion Act of 1975, we like our ounces, pounds, quarts, inches, and miles, thank you very much, they work. Now leave us alone. Take your liters and leave.

Constellation XIX: St. Gabriel the Archangel, formerly Pegasus.

But Coelum stellatum Christianum was valuable for other reasons beyond trying to wrest the stars out their pagan context and place them in accordance with Christian theology. Twenty-four years after Johann Bayer's Uranometria (1603) - at the time, the best star atlas - was published, Schiller corresponded with  Bayer and included corrections and additions to the stars and their positions. Coelum stellatum Christianum was, for instance, was first celestial atlas to include the Great Nebula in Andromeda. It was, upon its publication, the most accurate star atlas yet produced despite its biblical gloss.

Constellation Va: St. Sylvester, Pope, formerly Bootes.

The plates in Coelum stellatum Christianum are slightly smaller than those in Uranometria but presented in the same order.  A printed table lies opposite each map, and the stars are identified by Arabic numbers, rather than Bayer letters. Schiller provides two descriptions for each star, one referencing  the original pagan constellation figure, the other its new Christian identity.

Star chart I by Caspar Scheck.

"In considering Schiller's atlas it is convenient to distinguish between the scientific content and the religious orientation. Viewed simply as a collection of celestial maps it was the best available until Hevelius published his atlas 60 years later. Schiller was not himself an astronomer, but a cartographer who used the observations of others. His atlas, essentially a revision of Bayer's Uranometria, was based on the latest - the most extensive and the most accurate - astronomical information. Among his authorities were Tycho Brahe, Franciscus Pissero's revision of Tycho's catalogue as published by Grienberger, Galileo's telescopic observations of the Pleiades, and Simon Marius' telescopic observations of the Andromeda nebula. Kepler, it must be remembered, had not yet issued the expanded version of Tycho's catalogue and it was not apparent that he would ever do so (in fact, the Tabulae Rudolphinae appeared in the same year, 1627).

Star chart II by Caspar Scheck.

"Schiller's atlas was the outcome of the ideas and work of several men, extending over a quarter of a century. The need for a new atlas, with revised star positions and constellations, was argued by Bayer, Schiller, and Raymond Minderer, a doctor of medicine also at Augsburg. Bayer then undertook the astronomical revisions while Schiller, in correspondence with the Jesuit astronomers Johann Baptist Cysat, Paul Guldin, and Jesuits philologist and historian Matthew Rader, converted the Greco-Roman constellations into Judeo-Christian ones. Wilhelm Schickard, the astronomer and professor of Oriental languages at Tübingen, supplied the Arabic letters and star and constellation names. Kaspar Schecks positioned the stars on the copper plates, German historical painter Johann Mathias Kager drew the constellation figures, and Lucas Kilian engraved them. Finally Jakob Bartsch [Kepler's son-in-law] supplied various astronomical tables and, after Schiller's death, supervised publication" (Warner, D.K. The Sky Explored, pp. 229-230).

Despite Schiller's best efforts, ultimately the fate of Coelum stellatum Christianum and its Christianized constellations rested with the Old Gods. Their opinion was swift and stern.


SCHILLER, Julius. Coelum Stellatum Christianum Ad majorem Dei Omnipotentis, Sanctaeq Eius fam Triumphantis quam Militantis Ecclesiae Gloriam. Onductis Gentilium Simulachris, eidem Domino et Creatori Suo, postliminio quasi restitutum, Humili Conatu et Voto. Julii Schilleri Augustani Vindel V.I.D. ; sociali opera Joannis Bayeri IC Uranometriam novam, priore accuratorem, locupletioremq suppenditantis Matthiae Kageri, picturam primo concinnantis ; scalpello, qua imagines Lucae Kiliani, qua stellas Casparis Schecksii. [Augsburg]: Augustae Vindelicorum, Praelo Andreae Apergeri, 1627.

First edition. Oblong folio. (12 1/4 x 14 1/2 in; 313 x 367 mm). [4], 134, [1, errata], [1, blank] pp. Engraved title page, fifty-one celestial maps including  biblical constellation figures engraved by L. Kilian after M. Kagerone, one  engraved plate (Arabica Nomina). Includes Jakob Bartsch's Tabulae constellationum synopticae and Tabula canonica, and updated states of Schecksius' star charts.

Images courtesy of David Brass Rare Books, with our thanks.

The Linda Hall Library of Science, Engineering, and Technology has a Constellation Index of the originals and Schiller's Christian replacements along with digital reproductions of each of Schiller's maps.


  1. "Quoniam omnes dii gentium daemonia; Dominus autem caelos fecit." Psalm 95:5

  2. Quae cum ita sint, Dominus fecit mihi magna.

  3. For anyone interested in viewing this beautiful work of art, visit the Linda Hall Library (, choosing "Digital Collections", and then "Star Atlases" from the drop down menu presented to you.



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