Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Taurus |
Right ascension | 04h 23m 51.82553s[1] |
Declination | +09° 27′ 39.4939″[1] |
Apparent magnitude (V) | 5.098[2] (5.8 / 5.9)[3] |
Characteristics | |
Spectral type | A3V + A4V[4] |
U−B color index | +0.10[5] |
B−V color index | +0.07[5] |
Astrometry | |
Radial velocity (Rv) | −8.70±1[6] km/s |
Proper motion (μ) | RA: −20.32[1] mas/yr Dec.: −5.32[1] mas/yr |
Parallax (π) | 8.24 ± 0.31 mas[1] |
Distance | 400 ± 10 ly (121 ± 5 pc) |
Absolute magnitude (MV) | −0.32[7] |
Orbit[3] | |
Period (P) | 54.77 yr |
Semi-major axis (a) | 0.188″ |
Eccentricity (e) | 0.720 |
Inclination (i) | 34.2° |
Longitude of the node (Ω) | 239.8° |
Periastron epoch (T) | 1937.24 |
Argument of periastron (ω) (secondary) | 332.0° |
Details | |
66 Tau A | |
Mass | 2.89[8][note 1] M☉ |
Rotational velocity (v sin i) | 81[9] km/s |
66 Tau B | |
Mass | 2.76[8][note 1] M☉ |
Other designations | |
Database references | |
SIMBAD | data |
66 Tauri, also known as r Tauri, is a binary star in the constellation of Taurus. The combined apparent magnitude of the system is 5.098,[2] with the magnitudes of the two components being 5.8 and 5.9, respectively.[3] Parallax measurements by Hipparcos put 66 Tauri at some 400 light-years (121 parsecs) away.[1]
This is a visual binary where the positions of the two stars are tracked over time, and used to calculate an orbit. The two stars orbit each other every 55 years.[3] Their orbit is fairly eccentric, at 0.720, and the two stars are separated by 0.188″ on average.[3] Both stars are A-type main-sequence stars with similar masses.[8]
Cite error: There are <ref group=note>
tags on this page, but the references will not show without a {{reflist|group=note}}
template (see the help page).