Eridanus, which is a Latin name for the real Po River in Italy, is the sixth largest constellation in the night sky. It is one of the original 48 constellations described by Greek astronomer Ptolemy in the 2nd century.

The Babylonians may have inspired Eridanus with their "Star of Eridu" constellation. Eridu was an ancient city in Babylon known for its sacred marshes for the god Enki-Ea who ruled the domain of the Abyss. To the Greeks, it was associated with the myth of Phaethon who took the reins of his father Helios' sky chariot. Unfortunately, he did not have the strength to control it and veered wildly in different directions, scorching both heaven and earth. Eridanus is supposed to represent the path Phaethon took.

The named stars in Eridanus are, in order of brightness:

Achernar (α Eridani) is the ninth-brightest star in the night sky, a binary star system consisting of a blue giant and a blue-white giant. The system lies about 139 light years away. Its name comes from the Arabic phrase ākhir an-nahr meaning "the end of the river," since Achernar lies at the southern end of Eridanus.

Cursa (β Eridani) is at the northern end of the river, a blue-white giant star about 90 light years away. Its name comes from the Arabic phrase Al Kursiyy al Jauzah meaning "the chair of the central one."

Acamar (θ¹ Eridani) is a triple star system consisting of three blue-white giants about 167 light years away. The name comes from the Arabic phrase ākhir an-nahr meaning "the end of the river." The reflects the fact that Achernar is not visible from Greece, so Acamar was traditionally the end of the river.

Zaurak (γ Eridani) is a solitary red giant star about 192 light years away. Its name comes from the Arabic word zaurak meaning "boat."

Rana (δ Eridani) is an orange giant star about 30 light years away. Its name comes from the Latin word for "frog."

Ran (ε Eridani) is a solitary red dwarf star about 10 light years away. This is the third-closest star system visible to the naked eye. It has one confirmed exoplanet orbiting it, about the mass of Jupiter, named AEgir. Both names were given by 8th grade students in Colbert, Washington: Ran is the Norse goddess of the sea, and Ægir is the Norse god of the ocean.

Theemin (υ² Eridani) is a yellow giant star about 211 light years away. Its name comes from a corruption of the Greek words hē kampē meaning "the bend in the river."

Sceptrum (53 Eridani) is a binary star system about 110 light years away. It consists of at least one orange giant star. Its name is Latin for "scepter."

Azha (η Eridani) is an orange giant star about 137 light years away. Itts name comes from the Arabic phrase udḥiyy al-naʽām meaning "the ostrich nest."

Beemim (υ³ Eridani) is an orange giant star about 296 light years away. Its name shares the same origin as Theemin.

Beid (o¹ Eridani) is a yellow-white giant star about 122 light years away. It is also a variable star with irregular changes in brightness. Its name comes from the Arabic word bayḍ meaning "eggs."

Keid (o² Eridani) is a triple star system consisting of two red dwarfs and a white dwarf. The entire system lies about 16 light years away. Historically, this was the first white dwarf star to be discovered. Its name comes from the Arabic word alqayḍ meaning "eggshells."

Angetenar (τ² Eridani) is an orange giant star about 187 light years away. Its name comes from the Arabic phrase Al Ḥināyat an-Nahr meaning "the bend in the river."

Zibal (ζ Eridani) is a binary star consisting of two blue-white giant stars. The entire system lies about 110 light years away. Its name is a misreading of the Arabic word riʼal meaning "ostrich chicks."

Ayeyarwady (HD 18742) is a Sun-like star about 527 light years away. It has one confirmed exoplanet orbiting it, about 3.3 times the mass of Jupiter, named Bagan. Both names were given by the people of Myanmar: Ayeyarwady is a river in Myanmar, while Bagan is an ancient city on the banks of this river.

Mouhoun (HD 30856) is a binary star system consisting of a red giant and a red dwarf star. The entire system lies about 429 light years away. It has one confirmed exoplanet orbiting it, about 1.5 times the mass of Jupiter, named Nakanbé. Both names were given by the people of Burkina Faso: Mouhoun is the local name of the Black Volta river, while Nakanbé is the local name for the White Volta river.

Koeia (HIP 12961) is a red dwarf star about 76 light years away. It has one confirmed exoplanet orbiting it, about a third the mass of Jupiter, named Aumatex. Both names were given by the people of Puerto Rico: Koeia is the word for star in the language of the Taíno people, while Aumatex is the god of wind.

Montuno (WASP-79) is a Sun-like star about 780 light years away. It has one confirmed exoplanet orbiting it, named Pollera, about 80% the mass of Jupiter. Both names were given by the people of Panama: Montuno is a traditional costume a man wears during the "El Punto" dance, while Pollera is the traditional costume a woman wears.

Chaophraya (WASP-50) is a Sun-like star about 594 light years away. It has one confirmed exoplanet orbiting it, about 1.5 times the mass of Jupiter, named Maeping. Both names were given by the people of Thailand: both are rivers in Thailand.