5 Tauri

5 Tauri
Observation data
Epoch J2000      Equinox J2000
Constellation Taurus
Right ascension 03h 30m 52.38296s
Declination +12° 56 12.0489
Apparent magnitude (V) +4.14
Characteristics
Spectral type K0-III
U−B color index +0.95
B−V color index +1.09
Astrometry
Radial velocity (Rv)14.2±0.3 km/s
Proper motion (μ) RA: 13.537 mas/yr
Dec.: -2.037 mas/yr
Parallax (π)6.1081±0.3907 mas
Distance530 ± 30 ly
(160 ± 10 pc)
Absolute magnitude (MV)−0.96
Orbit
Primary5 Tauri A
Companion5 Tauri B
Period (P)960 days
Semi-major axis (a)4.25 mas
Eccentricity (e)0.397±0.016
Inclination (i)36.95°
Longitude of the node (Ω)207.61°
Periastron epoch (T)2,414,889.565±5.82
Argument of periastron (ω)
(secondary)
326.32±2.99°
Semi-amplitude (K1)
(primary)
8.25±0.15 km/s
Details
5 Tauri A
Mass4.0±0.7 M
Radius8.5 R
Luminosity329.38 L
Surface gravity (log g)1.97 cgs
Temperature4,644 K
Metallicity [Fe/H]0.05 dex
Rotational velocity (v sin i)10 km/s
5 Tauri B
Mass1.13±0.13 M
Other designations
f Tau, 5 Tau, BD+12°486, FK5 125, GC 4184, HD 21754, HIP 16369, HR 1066, SAO 93469, TYC 656-1725-1
Database references
SIMBADdata

5 Tauri is a binary star in the zodiac constellation of Taurus, located approximately 530 light years from the Sun. It is visible to the naked eye as a faint orange-hued star with an apparent visual magnitude of +4.14. It is moving further from the Earth with a heliocentric radial velocity of +14 km/s.

This is a spectroscopic binary with a period of 960 days and an eccentricity of about 0.4. The primary component is a K-type giant with a stellar classification of K0-III. It has four times the mass of the Sun and is radiating 329 times the Sun's luminosity from its photosphere at an effective temperature of 4,644 K.