It's time for another constellation: Piscis Austrinus: the great (or 'Southern') fish. It's also known as Piscis Australis, and prior to the 20th century, it was known as Piscis Notius. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and it remains one of the 88 modern constellations. The stars of the modern constellation Grus once formed the 'tail' of Piscis Austrinus.

In Hellenic mythology, this constellation is known as the Great Fish and it is portrayed as swallowing the water being poured out by Aquarius, the water carrier. The two fish of the constellation Pisces are said to be the offspring of the Great Fish. From Hyginus' 'Astronomica' comes the follow reason for his placement in the sky:

This is the Fish that is called Southern. He seems to take water in his mouth from the sign of Aquarius. Once, when Isis was in labor, he is thought to have saved her, and as a reward for this kindness she placed the fish and its young, about whom we have spoken before, among the stars. As a result the Syrians generally do not eat fish, and worship their gilded likenesses as household gods. Ctesias, too, writes about this. [II.41]

Aratos, too, confirms the position of the Great Fish in his 'Phaenomena'. Amongst other mentions, he writes:

"Below Aegoceros before the blasts of the South Wind swims a Fish, facing Cetus, alone and part from the former Fishes; and him men call the Southern Fish. Other stars, sparsely set beneath Hydrochoüs [Aquarius], hang on high between Cetus in the heavens and the Fish, dim and nameless, and near them on the right hand of bright Hydrochoüs, like some sprinked drops of water lightly shed on this side and on that, other stars wheel bright-eyed though weak." [385 - 389]

Needless to say, this is a minor constellation. It is visible at latitudes between +55° and −90°, and best visible at 21:00 (9 p.m.) during the month of October.