River Tigris (constellation)

The Tigris River (Latin tigris) is a constellation of the northern sky, which is not among the 88 of the International Astronomical Union ( IAU) recognized constellations.

The Tigris starts in the western part of the constellation Pegasus, includes the entire constellation Fox ( Vulpecula ) and some eastern stars of the constellations Hercules and Ophiuchus.

The brightest stars of the constellation are: 72 Ophiuchi 3.71 m, 3.85 m and 1 109 Herculis Pegasi 4.08 m. The remaining stars are very faint, a maximum of 4.2 m size class, mostly 5m size class or weaker.

The river Tigris in 1612 presented by the Dutch theologian, astronomer and cartographer Petrus Plancius on a celestial globe made ​​by him, as Füllsternbild between eagle, Pegasus, swan and Hercules. In addition to the mythical Eridanus by Ptolemy, who was called by Keyser Nile, led Plancius the Jordan River, and this was presumably the one of the four rivers of Paradise.

Heavenly Tigris it has no resemblance to the true course of the river of earthly Tigris River. This is probably why, and also because there was already a river in the sky, which was introduced by the Danzig astronomer Johannes Hevelius Fuchs was preferred as Füllsternbild for this star area.

In Europe, the Tigris shows in the summer night sky.