Eridanus Constellation

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Eridanus (Greek: a mythical river associated with Phaëton) is the sixth largest of the 88 modern constellations. It was also one of Ptolemy's 48 constellations. At its southern end is the first magnitude star Achernar. Achernar is a very peculiar star because it is one of the flattest stars known. Observations indicate that its radius is about 50% larger at the equator than at the poles. Responsible for this is the fact that Achernar is spinning extremely fast.