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A pale yellow star shining relatively faintly in the northern regions of Eridanus, near the point where the constellation of the River approaches bright Rigel at the foot of Orion. 64 Eridani lies somewhat southward of Rigel, almost on the eastern border of Eridanus where it meets Lepus the Hare, which lies directly to the south of Orion.

64 Eridani is rather more luminous than the Sun, emitting about eighty times as much light, and being about six times the Sun's diameter. It is variously classed as a highly luminous dwarf star or as a subgiant. The star lies some 272 light years from the Solar System (based on the recent Gaia parallax data, which places it a little closer than the previous value of about 290 light years).

64 Eridani is a rapidly-rotating star, and this rotation causes a flattening of its form to create a distinctly oblate shape. Regular patterns of pulsation pass through the star, causing its brightness to vary over a period of some six-and-a-half hours, and it thus carries the alternative variable designation of 'S Eridani'. There is some uncertainty over its particular class of variability; most sources classify this star as a Delta Scuti variable, but others prefer to define it as an RR Lyrae variable (which would be rather an exotic classification for a star with the characteristics of 64 Eridani).


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