Tau3 Eridani
A-type star in the constellation Eridanus
From Wikipedia, the free encyclopedia
Tau3 Eridani, Latinized from τ3 Eridani, is a star in the constellation Eridanus. It is visible to the naked eye with an apparent visual magnitude of 4.10.[2] Using the parallax method,[1] the distance to this star can be estimated as 88.6 light years. In 2001 it was reported as a candidate Vega-like star, meaning it appears to radiate an infrared excess from an orbiting circumstellar disk.[12] However, this has not been confirmed.[13]
 | |
| Observation data Epoch J2000.0 Equinox ICRS | |
|---|---|
| Constellation | Eridanus |
| Right ascension | 03h 02m 23.49939s[1] |
| Declination | −23° 37′ 28.0936″[1] |
| Apparent magnitude (V) | 4.10[2] |
| Characteristics | |
| Evolutionary stage | main sequence[3] |
| Spectral type | A3 IV-V[4] |
| U−B color index | +0.08[2] |
| B−V color index | +0.16[2] |
| Astrometry | |
| Radial velocity (Rv) | −9.8[5] km/s |
| Proper motion (μ) | RA: −147.25[1] mas/yr Dec.: −55.28[1] mas/yr |
| Parallax (π) | 36.80±0.18 mas[1] |
| Distance | 88.6 ± 0.4 ly (27.2 ± 0.1 pc) |
| Absolute magnitude (MV) | +1.91[6] |
| Details | |
| Mass | 1.78[7] M☉ |
| Radius | 1.9[8] R☉ |
| Luminosity | 13.7[9] L☉ |
| Surface gravity (log g) | 4.17[7] cgs |
| Temperature | 8,251±281[7] K |
| Metallicity [Fe/H] | −0.21[4] dex |
| Rotational velocity (v sin i) | 133[10] km/s |
| Age | 476[7] Myr |
| Other designations | |
| τ3 Eri, 11 Eri, CD−24 1387, CPD−24 358, GJ 121, HD 18978, HIP 14146, HR 919, SAO 168249[11] | |
| Database references | |
| SIMBAD | data |
This is an A-type star with a stellar classification of A3 IV-V.[4] The luminosity class of IV-V indicates the spectrum displays traits intermediate between a main sequence and subgiant star. It is around 476[7] million years old and is spinning rapidly with a projected rotational velocity of 133 km/s.[10] This is creating an equatorial bulge that might be 7% wider than the polar radius.[14] Tau3 Eridani has 178%[7] of the Sun's mass and nearly double the radius of the Sun.[8] The star shines with 13.7 times the solar luminosity from an outer atmosphere at an effective temperature of 8,251 K.[7]