ERIDANUS

Phaethon, son of Helios the Sun God, pestered his father to allow him to drive the celestial chariot across the skies one day. (The sun was seen as carried daily on a chariot driven by Helios.) Phaethon was encouraged by his sisters and even his own mother. But Helios always refused, knowing that his son was far from ready to assume such an awesome responsibility.

However under the constant pleading by Phaethon, Helios eventually relented. So one day Phaethon climbed into the chariot, drawn by two white horses. He grasped the reins and set off across the skies. But it was soon apparent that Phaethon was incapable of controlling the horses, which galloped so high in the sky that the earth was close to freezing, then plunged so close to the earth that the fields were burnt.

Zeus quickly had enough of this nonsense and sent a thunderbolt, killing the young driver. Phaethon fell into the sacred river Eridanus while his sisters, for having encouraged him in this foolhardy adventure, were changed into poplar trees which stood along its banks.

The evenings of October are a good time to see most of the night sky's water world, a region in which all the constellations relate to water: a river, Eridanus, a person who carries water, a shore bird, and six critters who live in the sea. It's a huge region stretching from Capricornus, which is next to the summer sky's Sagittarius, to Eridanus which is next to winter's Orion.

Although one of the largest sky regions, it's also one of the faintest, composed mostly of stars that can be seen only under very dark skies. The entire region contains but one bright, 1st-magnitude star visible from our latitude.

The star Achenar is the brightest star in the constellation, but by far not the best means to notice it. In the night sky, locate Orion, by its belt and Rigel. The line between Rigel and the middle star in the belt makes a line. This line is one side of a trapezoidal square shape. Cursa, the second brightest star in Eridanus, makes up one of the adjacent corners of the square. The last star is irrelevant.

Achenar is the star with the lowest magnitude in Eridanus, thus being the brightest. Its apparent magnitude, as seen from earth, is 0.45, and its absolute magnitude is –2.77. The constellation Eridanus contains the faintest know star, a brown dwarf. A team of scientists who were looking for dim stars, just happened to find this star, which was soon decided o be the dimmest star ever discovered. Also, it just happened to be in the constellation Eridanus.