Blue-white main-sequence star · Eridanus
υ⁴ Eridani
Also known as: υ⁴ Eri, HIP 20042
mag 3.6180 light-years
About
υ⁴ Eridani is a blue-white main-sequence star of magnitude 3.6 in Eridanus, about 180 light-years away.
How to find it
- υ⁴ Eridani is in the constellation Eridanus.
- Best evenings: around early January it is highest at about 9 pm (10 pm in summer time); a month earlier, two hours later.
- Where on Earth: it is seen well, at least 10° up, from south of 46° N.
When it rises and sets tonight, how high it climbs and how much the Moon gets in the way are worked out in your browser for your place.
What you will see
- EyesVisible from the suburbs on a clear night, but lost in bright city skies.
- Binoculars (10×50)A sharp point; binoculars bring out its colour and the fainter stars around it.
- Telescope (6–8 inch)Still a point of light at any magnification — stars are too far away to show a disc. Low in the sky, bright stars twinkle and flash colours.
Stars look the same in any instrument: brighter and sharper, but never bigger.
Facts
| Designation | υ⁴ Eridani (υ⁴ Eri) |
|---|---|
| Hipparcos number | HIP 20042 |
| Type | Blue-white main-sequence star |
| Spectral type | B9V |
| Colour | Blue-whiteB−V colour index −0.11 |
| Magnitude | 3.6The smaller the number, the brighter. |
| Distance | 180 light-yearsThe light you see left it around 1850. |
| Proper motion | 0.063″ per year across the sky |
| Constellation | Eridanus |
| Right ascension (J2000) | 04h 17m 53.7s |
| Declination (J2000) | −33° 47′ 54″ |
Sources and credits
Star data: HYG Database by David Nash, CC BY-SA 4.0. All data sources →