Stars · Star in Eridanus
Star
Achernar
“The river’s end” — the last star of Eridanus — and one of the flattest stars known, spinning so fast it is squashed like a lens.
- Constellation
- Eridanus
- Designation
- α Eridani
- Apparent magnitude
- 0.45 · 9th brightest star in the night sky
- Spectral class
- B3Vp
- Distance
- 139 light-years
- Position (J2000)
- RA 1h 38m · Dec −57° 14′
A blue-white main-sequence star, around 24,000 K, like Rigel and Spica. About 260× brighter than the faintest star the eye can see. The light you are seeing left around 1887.
Science
It turns at over 250 km/s at its equator, close to the speed that would fling it apart, and it sheds a disc of gas from its waist.
Did you know
From Sydney, Cape Town and Buenos Aires it never sets — it just circles the south pole of the sky.