Wednesday, June 28, 2023

Hevelius Introduced Three-Headed Snake Constellation Cerberus in 1687


Summary: Johannes Hevelius introduced Cerberus the Three-Headed Snake constellation in 1687 as a starry monster grasped by Hercules the Hero's left hand.


Hercules the Hero (center) with Cerberus the Three-Headed Snake (center right) and Vulpecula the Fox with Anſer (Anser) the Goose (right center); Hevelius's depiction from perspective of outsider looking into celestial globe reverses actual east-west appearance of sky for Earth-based observer as insider looking outward at celestial globe; J. Hevelii, Firmamentum Sobiescianum (MDCXC [1690]), Fig. H: Public Domain, via ETH-Bibliothek e-rara

Seventeenth-century Polish astronomer Johannes Hevelius introduced Cerberus the Three-Headed Snake constellation in 1687 as a starry monster held captive in the firm grasp of constellation Hercules the Hero's left hand.
Johannes Hevelius (Polish: Jan Heweliusz; Jan. 28, 1611-Jan. 28, 1687) featured Cerberus the Three-Headed Snake constellation as one of 10 constellations that he had visualized in Prodromus Astronomiae. The three-volume compendium comprised the Prodromus; a star catalogue, Catalogus Stellarum Fixarum; and a star atlas, Firmamentum Sobiescianum sive Uranographia. Hevelius's death left the Prodromus Astronomiae unfinished and the catalogue and star atlas, which had been printed in 1687, unpublished. The astronomer-selenographer's wife, Polish astronomer Elisabeth Catherina Koopmann Hevelius (Polish: Elżbieta Koopman Heweliusz; Jan. 17, 1647–Dec. 22, 1693), finished the Prodromus and then published all three volumes, under the sole authorship of her husband, in 1690.
Hevelius presented Cerberus as the ninth of his 10 newly created constellations in Chapter VIII, De Numero Aſteriſmorum & Stellarum, tum nonnullis Rebus animadverſione dignis, of section Tabulae Solares Novae ("New Solar Tables") in the Prodromus. Although he described Cerberus as a "triple-headed, infernally voracious dog," Hevelius depicted the constellation as a three-headed snake.
In Greek mythology, Cerberus represented the last of the 12 labors undertaken by Hercules (Heracles; Greek: Ἡρακλῆς, Hēraklḕs, "glory of Hera") as penance for his Hera-induced rageful murder of his wife, Theban Princess Megara (Ancient Greek: Μεγάρα), and their sons. Cerberus (Greek: Κέρβερος Kérberos) was a three-head dog, with a serpentine tail and a profusion of snakes protruding from his body and mane, who ferociously guarded the gates of the Underworld to foil escape attempts by the souls of the dead.

Anser and Vulpecula (center) with Hercules (upper left) and Cerberus (left center); Hevelius's depiction from perspective of outsider looking into celestial globe reverses actual east-west appearance of sky for Earth-based observer as insider looking outward at celestial globe; J. Hevelii, Firmamentum Sobiescianum (MDCXC [1690]), Fig. L: Public Domain, via ETH-Bibliothek e-rara

Hevelius connected his ninth new constellation, Cerberus, with his eighth constellatory creation, double-figured Vulpecula the Fox and the Anser the Goose. With the stolen Goose in his mouth, the Fox runs swiftly to gift voracious Cerberus with his captive anserous prey.
"De Cerbero. Dicta haec Vulpecula, furto ſurripuit Anſerem, quam in ore gerens veloci curſu ad Cerberum, Tricipitem nempe illum Canem infernalem voracem deportat, quò Jentaculum & ſolatium quaſi habeat, antequam ab Hercule clavamjam exporrigente, occidatur. Sic ut haec Vulpecula cum Anſere, etiam juxta fabulas Poetarum, & Aſtrologorum Regulas, convenienter hoc loco reponi à me potuerit. Haud minùs benè factum, quòd Herculi, Cerberum ſiniſtrâ manu tenendum tradiderim," Hevelius explained (page 117).
Hevelius depicted his Cerberus constellation in five illustrations in Firmamentum Sobiescianum, the third volume of Prodromus Astronomiae. The main depiction, in Tavola H, centers on Hercules the Hero with Cerberus the Three-Headed Snake in his left hand and with neighbors Vulpecula the Fox and Anser the Goose. Tavola I focuses on Lyra the Lyre with neighbors Hercules and Cerberus. Tavola L centers on Anser and Vulpecula with neighbors Hercules and Cerberus. Tavola P depicts Hercules and Cerberus as neighbors of Serpentarius, alternative name of Ophiuchus the Serpent Bearer. Tavola R shows Cerberus and Vulpecula with Anser as neighbors of Aquila the Eagle and Antinous the Lover of Roman Emperor Hadrian.

Aquila (center) with Cerberus (upper left) and Vulpecula (upper right) with Anser (upper center); Hevelius's depiction from perspective of outsider looking into celestial globe reverses actual east-west appearance of sky for Earth-based observer as insider looking outward at celestial globe; J. Hevelii, Firmamentum Sobiescianum (MDCXC [1690]), Fig. R: Public Domain, via ETH-Bibliothek e-rara

As with all of Hevelius's constellations, figures are reversed, depicted "back to front," as if on a celestial globe, as noted by English constellation history biographer Ian Ridpath (born May 1, 1947) in his post on "Hevelius and Firmamentum Sobiescianum" on his Star Tales website. Depictions from the perspective of an outsider looking into a celestial globe reverse, or create mirror images of, the actual appearance of starry figures as viewed by an Earth-based observer situated as an insider looking outward at a celestial globe.
Hevelius created Cerberus from four faint stars in southwestern Hercules the Hero constellation. The cerberic quartet comprised the quartet known modernly as 93 Herculis (93 Her), 95 Herculis (95 Her), 102 Herculis (102 Her) and 109 Herculis (109 Her), according to Ian Ridpath's "Cerberus" in Chapter Four: Obsolete Constellations on his Star Tales website.
The quartet's moderate brightness allows for visibility in dark sky locations and bare or no visibility in light pollution-affected skies, according to Iacopo Sassarini's The Sky Live website. Hypergiant 93 Herculis and variable, visual double 109 Herculis are orangeish yellow hued. Variable, double giant 95 Herculis casts a white-hued light. Double sub-giant 102 Herculis is blue-white hued.
Four constellations arc around Hercules-held Cerberus the Three-Headed Snake. Ophiuchus the Serpent Bearer, known to Hevelius as Serpentarius, neighbors to the south. Aquila the Eagle flies to the southwest of the Three-Headed Snake. To the west, Vulpecula the Fox bears mouth-held prey Anser the Goose while Sagitta the Arrow targets westward, away from Cerberus. Lyra the Lyre lies to the west-northwest.

Serpentarius (center) with Hercules (center left) and Cerberus (center right); Hevelius's depiction from perspective of outsider looking into celestial globe reverses actual east-west appearance of sky for Earth-based observer as insider looking outward at celestial globe; J. Hevelii, Firmamentum Sobiescianum (MDCXC [1690]), Fig. P: Public Domain, via ETH-Bibliothek e-rara

Cerberus is considered an obsolete constellation. The Three-Headed Snake constellation did not number among the 88 modern constellations approved by the International Astronomical Union's (IAU) inaugural General Assembly, held May 1922 in Rome, Italy.
Although constellation Cerberus has been disbanded and re-absorbed as unfigured stars in constellation Hercules, the quartet's presence in night skies remains. Skygazers still may improve their unaided or aided eyesight by embellishing Hercules with a serpentine captive.
As part of constellation Hercules, Cerberus shares the Hero's visibility range. Full visibility is available for observers located between latitudes 90 degrees north and 38 degrees south. Observers at latitudes 38 degrees south to 86 degrees south experience partial visibility of the Hero, according to Ian Ridpath's "Constellations -- 1" table on his Star Tales website.
Hercules the Hero encompasses an area of 1,225.1 square degrees, which claims 2.970 percent of the area of the night sky. The Hero's areal spread accords it placement as the fifth largest of the 88 constellations recognized by the International Astronomical Union (IAU).
Right ascension (abbreviated RA; symbol α) coordinates for the Herculean constellation extend from 15 hours (h) 48 minutes (m) 29.9005 (s) to 18h 57m 49.5029s, according to the constellation boundary tables on the International Astronomical Union's website. The equatorial coordinate system's right ascension likens to terrestrial longitude.
Declination (abbreviated dec; symbol δ) coordinates for constellation Hercules span plus 3.6735139 to plus 51.3242683. In the equatorial coordinate system, declination similarizes to geographic latitude.
April through November qualify as best Herculean viewing months for Northern Hemisphere observers. Hercules favors June through September as best viewing months for Southern Hemisphere skygazers, according to James Miller in "Star Constellation Facts: Hercules," posted April 14, 2015, to his website, Astronomy Trek.
Hercules climbs especially high in the sky through the summer in Northern Hemisphere skies. The constellation's Herculean height facilitates sighting of its Keystone asterism. The quadrilateral comprises Epsilon Herculis (ε Herculis; abbreviated ε Her, Epsilon Her), Zeta Herculis (ζ Herculis; abbreviated ζ Her, Zeta Her), Eta Herculis (η Herculis; abbreviated η Her, Eta Her) and Pi Herculis (π Herculis; abbreciated π Her, Pi Her). The Keystone outlines the Hero's pelvis, according to Ridpath's "Stars of Hercules" in Chapter Three: The Celestial Eighty-Eight on his Star Tales website. The Keystone lies to the northeast of Cerberus.

Lyra (center) with Hercules (left) and Cerberus (lower left); Hevelius's depiction from perspective of outsider looking into celestial globe reverses actual east-west appearance of sky for Earth-based observer as insider looking outward at celestial globe; J. Hevelii, Firmamentum Sobiescianum (MDCXC [1690]), Fig. I: Public Domain, via ETH-Bibliothek e-rara

Acknowledgment
My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:
Hercules the Hero (center) with Cerberus the Three-Headed Snake (center right) and Vulpecula the Fox with Anſer (Anser) the Goose (right center); Hevelius's depiction from perspective of outsider looking into celestial globe reverses actual east-west appearance of sky for Earth-based observer as insider looking outward at celestial globe; J. Hevelii, Firmamentum Sobiescianum (MDCXC [1690]), Fig. H: Public Domain, via ETH-Bibliothek e-rara @ https://www.e-rara.ch/zut/content/zoom/133895
Anser and Vulpecula (center) with Hercules (upper left) and Cerberus (left center); Hevelius's depiction from perspective of outsider looking into celestial globe reverses actual east-west appearance of sky for Earth-based observer as insider looking outward at celestial globe; J. Hevelii, Firmamentum Sobiescianum (MDCXC [1690]), Fig. L: Public Domain, via ETH-Bibliothek e-rara @ https://www.e-rara.ch/zut/content/zoom/133901
Aquila (center) with Cerberus (upper left) and Vulpecula (upper right) with Anser (upper center); Hevelius's depiction from perspective of outsider looking into celestial globe reverses actual east-west appearance of sky for Earth-based observer as insider looking outward at celestial globe; J. Hevelii, Firmamentum Sobiescianum (MDCXC [1690]), Fig. R: Public Domain, via ETH-Bibliothek e-rara @ https://www.e-rara.ch/zut/content/zoom/133913
Serpentarius (center) with Hercules (center left) and Cerberus (center right); Hevelius's depiction from perspective of outsider looking into celestial globe reverses actual east-west appearance of sky for Earth-based observer as insider looking outward at celestial globe; J. Hevelii, Firmamentum Sobiescianum (MDCXC [1690]), Fig. P: Public Domain, via ETH-Bibliothek e-rara @ https://www.e-rara.ch/zut/content/zoom/133909
Lyra (center) with Hercules (left) and Cerberus (lower left); Hevelius's depiction from perspective of outsider looking into celestial globe reverses actual east-west appearance of sky for Earth-based observer as insider looking outward at celestial globe; J. Hevelii, Firmamentum Sobiescianum (MDCXC [1690]), Fig. I: Public Domain, via ETH-Bibliothek e-rara @ https://www.e-rara.ch/zut/content/zoom/133897

For further information:
Allen, Richard Hinckley. "Cerberus. . . . This sub-constellation, a former adjunct of Hercules, but now entirely disregarded by astronomers, is supposed to have originated with Hevelius in his Firmamentum Sobiescianum, although Flammarion asserts that it was on the sphere of Eudoxos with the Branch. . . . it probably was only made for the purpose of mythological completeness, as the death of this watch-dog of Hades fitly rounded out the circle of Hercules' twelve labors. Others have said that the figure typified the serpent destroyed by the Hero while it was infesting the country around Taenarum, the Μέτωπον of Greece, the modern Cape Matapan." Pages 159-160. Star-Names and Their Meanings. New York NY; Leipzig, Germany; London, England; Paris, France: G.E. Stechert, 1899.
Available via Internet Archive @ https://archive.org/details/starnamesandthe00allegoog/page/159/mode/1up
Available via Penelope-University of Chicago @ https://penelope.uchicago.edu/Thayer/E/Gazetteer/Topics/astronomy/_Texts/secondary/ALLSTA/Cerberus*.html
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Hevelii, Johannis. "Cur Vulpecula cum Anſere eo in loco fuerit rejecta. Ex Stellis autem iſtis, quae inter Aquilam & Lyram, ſub Cygno, haud procul à Cerbero, horribili illo & voraci animali, vel à Cane infernali Tricipiti (prout Poetae fabulantur) videntur, numero 27, nimirùm cum unâ olim jam cognitâ, & 26 novis meis à me ſolummodò obſervatis, ſimul cum illâ planè novâ, quae Anno primùm 1672 apparuit, ac per biennium in Coelo fulſit, volui Vulpeculam cum Anſere, in ſpatio Coeli benè apto, & quidem tale animalculum quod admodùm Aſtutum, vorax, & furax eſt, reponere. Attento, quòd Aquila & Lyra ejusdem ſint naturae; nimirùm rapaces & edaces: ne non & hae Stellae in Vulpeculâ, cum illis in Aquilâ & Lyrâ conſtitutis, eandem conſeervent naturam." Page 117. Prodromus Astronomiae cum Catalogo Fixarum, & Firmamentum Sobiescianum: Prodromus Astronomiae . . . Quibus additus est uterq[ue] Catalogus Stellarum Fixarum, tam major ad Annum 1660, quàm minor ad Annum completum 1700. Acceſſ Corollarii loco Tabula Motus Lunae Libratorii, Ad bina ſecula proximè ventura prolongata, brevi cum Deſcriptione, ejus ue uſu. Tabulae Solares Novae, pages 51-142. Caput VIII De Numero Aſteriſmorum & Stellarum, tum nonnullis Rebus animadverſione dignis," pages 108-124. Gedani [Gdansk]: Typis Johannis-Zachariae Stollii, M DC XC [1690].
Available via ETH-Bibliothek e-rara @ https://www.e-rara.ch/zut/content/zoom/133609
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Hevelii, Johannis. "De Cerbero. Dicta haec Vulpecula, furto ſurripuit Anſerem, quam in ore gerens veloci curſu ad Cerberum, Tricipitem nempe illum Canem infernalem voracem deportat, quò Jentaculum & ſolatium quaſi habeat, antequam ab Hercule clavamjam exporrigente, occidatur. Sic ut haec Vulpecula cum Anſere, etiam juxta fabulas Poetarum, & Aſtrologorum Regulas, convenienter hoc loco reponi à me potuerit. Haud minùs benè factum, quòd Herculi, Cerberum ſiniſtrâ manu tenendum tradiderim." Page 117. Prodromus Astronomiae cum Catalogo Fixarum, & Firmamentum Sobiescianum: Prodromus Astronomiae . . . Quibus additus est uterq[ue] Catalogus Stellarum Fixarum, tam major ad Annum 1660, quàm minor ad Annum completum 1700. Acceſſ Corollarii loco Tabula Motus Lunae Libratorii, Ad bina ſecula proximè ventura prolongata, brevi cum Deſcriptione, ejus ue uſu. Tabulae Solares Novae, pages 51-142. Caput VIII De Numero Aſteriſmorum & Stellarum, tum nonnullis Rebus animadverſione dignis," pages 108-124. Gedani [Gdansk]: Typis Johannis-Zachariae Stollii, M DC XC [1690].
Available via ETH-Bibliothek e-rara @ https://www.e-rara.ch/zut/content/zoom/133609
Available via National Digital Library Polona @ https://polona.pl/item-view/049ab5c8-5726-4a52-ad1b-48f3f475c4f2?page=73
Available via Google Books Read Free of Charge @ https://www.google.com/books/edition/JOHANNIS_HEVELII_PRODROMUS_ASTRONOMIAE/OEPatgAACAAJ?hl=en&gbpv=1&printsec=frontcover
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Available via ETH-Bibliothek e-rara @ https://www.e-rara.ch/zut/content/zoom/133777
Available via Google Books Read Free of Charge @ https://www.google.com/books/edition/JOHANNIS_HEVELII_PRODROMUS_ASTRONOMIAE/OEPatgAACAAJ?hl=en&gbpv=1&printsec=frontcover
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Available via ETH-Bibliothek e-rara @ https://www.e-rara.ch/zut/content/zoom/133784
Available via Google Books Read Free of Charge @ https://www.google.com/books/edition/JOHANNIS_HEVELII_PRODROMUS_ASTRONOMIAE/OEPatgAACAAJ?hl=en&gbpv=1&printsec=frontcover
Available via Linda Hall Library of Science, Engineering & Technology Catalog @ https://catalog.lindahall.org/discovery/delivery/01LINDAHALL_INST:LHL/1284873740005961
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