15 Eridani, an orange giant star in Eridanus
15 Eridani is an orange giant star in the constellation Eridanus. At 460 light years away, it shines at an apparent visual magnitude of 4.88.
15 Eridani (HIP 15382)
15 Eridani is an orange giant star in the constellation Eridanus. At 460 light years away, it shines at an apparent visual magnitude of 4.88. It is moving through the Galaxy at a speed of 18.5 km/s relative to the Sun.
Sky position: RA 3h 18.4m, Dec -22° 30.7'
Common designations: 15 Eridani, HR 994, HD 20610, Gaia DR3 5099265828450228864, HIP 15382
15 Eridani has the spectral type K0III. K-type stars are orange stars with surface temperatures of about 3,900 to 5,300 K. Their spectra are rich in neutral metal lines and, in the cooler examples, molecular bands. Its luminosity class III marks it as a giant: an evolved star that has left the main sequence and swollen to many times its original size.
How to find 15 Eridani in the sky
15 Eridani lies in Eridanus. With a declination of -22° 30.7', it is visible from the entire Southern Hemisphere and from the Northern Hemisphere up to about latitude 67° N. It is bright enough to see with the naked eye under dark skies. It is highest in the sky at local midnight around December, which makes the weeks around that month the best time to observe it.
Tabulated data for 15 Eridani
Astrometry and spectroscopy
| Right Ascension (J2000) | 49.59212561° (3h 18.4m) |
| Declination (J2000) | -22.51110428° (-22° 30.7') |
| Galactic Longitude | 213.25819896° |
| Galactic Latitude | -56.45991662° |
| Proper motion RA | 5.73 mas/yr |
| Proper motion Dec | 8.97 mas/yr |
| Parallax | 7.08 ± 1.47 mas |
| Spectral Type | K0III |
| Radial Velocity | 17.11 km/s |
Photometry
| Band | Magnitude | Abs. Mag. |
|---|---|---|
| B | 5.78 | 0.03 |
| V | 4.88 | -0.87 |
| J | 3.40 | -2.34 |
| H | 2.84 | -2.90 |
| K | 2.74 | -3.01 |
Colour index B-V: +0.91
Derivations
- Heliocentric distance: 141.17 pc (460 light years) (20.7% margin of error)
- Absolute visual magnitude: -0.87
- Transverse velocity: 7.1 km/s
- Space velocity relative to the Sun: 18.5 km/s
- Galactic position (X, Y, Z): -65.2 pc, -42.8 pc, -117.7 pc
- Galactic velocity (U, V, W): -14.2 km/s, -3.6 km/s, -11.3 km/s
Data: Extended Hipparcos Compilation (XHIP) and SIMBAD.