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The Jordan River

Jordanis is a now obsolete constellation in the northern hemisphere, created in 1612 by Petrus Plancius.

Jordanis, on some maps called Jordanus or Jordanus Fluvius was one of the most elaborate designs by Dutch-Flemish astronomer and cartographer Petrus Plancius.

Ptolemy's descriptions of the constellations covered only the brightest stars, leaving a larger number of stars between the constellations unused or "unformed." Plancius connected a number of unformed stars surrounding the main stars of Ursa Major to represent the Jordan River.

By modern designation, these stars are α CVn, 72 Leo, 54 Leo, 46 LMi, β LMi, 21 LMi, α Lyn, 38 Lyn, 10 UMa, 31 Lyn, 21 Lyn, 15 Lyn and 2 Lyn.

In Plancius' design, the river originated at a star now known as Cor Caroli the brightest light in the constellation Canes Venatici and ended near the constellation Camelopardalis, - another one of Plancius' creations.

Plancius' constellations were first introduced on one of his own globes in 1612, then in 1613 on a celestial globe published by Pieter van den Keere and then again in 1621 on a globe by Isaac Habrecht II.

In 1624, German astronomer Jakob Bartsch (son-in-law of famous Johannes Kepler) was the first to put the new constellations on maps in his book Usus Astronomicus Planisphaerii Stellati (Astronomical Use of the Stellar Planisphere).

Bartsch wrote that the river had two headwaters, Jor and Dan. They were not shown in Bartsch's map, but were displayed in Andreas Cellarius' famous Harmonia Macrocosmica. 100 years after Jordanis first appeared on a map, The German cartographer and globe maker Johann Ludwig Andreae had the river flow in the opposite direction, placing the headwaters of the river next to the head of Ursa Major.
Jordanis on a globe by Johann Ludwig Andreae, 1715
Source: Google Arts and Culture

Andreae's planisphere, 1724 (highlighted by the author)
Source: Ian Ridpath

Mirrored image of Jordanis in Harmonia Macrocosmica, 1660
Source: Wikimedia
Face-on image of Fluvius Jordanus by Carel Allard, 1706
In the late 1600s, wenn Polish astronomer Johannes Hevelius designed the constellations Canes Venatici, Leo Minor and Lynx, he used the stars of the Jordan River. And when Hevelius' constellations were shown in Johann Elert Bode's trendsetting star map Uranographia, Plancius' Jordan River ran dry.

Sources: John C. Barentine: The Lost Constellations, Ian Ridpath, Wikipedia
Jordan River;

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