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Eridanus is the sixth largest of the 88 modern constellations.
Eridanus is associated with two greek myths, both likely to be derived from the shape of the constellation - that of very twisty path.
Eridanus was sometimes considered to be a river which flowed from the waters of Aquarius, and in such situations, Aquarius was deigned to face Eridanus (requiring a change of angle, and thus redesign of how the stars of Aquarius connect, so that the water poured onto the same side as Eridanus).