41 Tauri
41 Tauri is a single-lined spectroscopic binary system in the zodiacal constellation of Taurus; 41 Tauri is its Flamsteed designation. The star has a visual magnitude of 5.19, making it visible to the naked eye from brighter suburban skies (according to the Bortle scale). Parallax measurements put it at a distance of roughly 404 light years from the Sun.
41 Tauri is the brightest star on the right of the molecular cloud LBN 777. | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Taurus |
| Right ascension | 04h 06m 36.413s |
| Declination | +27° 35′ 59.64″ |
| Apparent magnitude (V) | 5.19 |
| Characteristics | |
| Spectral type | B9 p Si |
| U−B color index | −0.47 |
| B−V color index | −0.12 |
| Variable type | α2 CVn |
| Astrometry | |
| Radial velocity (Rv) | −2.0 km/s |
| Proper motion (μ) | RA: +21.153 mas/yr Dec.: −51.792 mas/yr |
| Parallax (π) | 8.0667 ± 0.1063 mas |
| Distance | 404 ± 5 ly (124 ± 2 pc) |
| Orbit | |
| Period (P) | 7.2274 d |
| Eccentricity (e) | 0.18 |
| Semi-amplitude (K1) (primary) | 16.60 km/s |
| Details | |
| Mass | 2.9 M☉ |
| Radius | 3.54 R☉ |
| Luminosity | 190 L☉ |
| Surface gravity (log g) | 3.87 cgs |
| Temperature | 12,600 K |
| Metallicity [Fe/H] | 0.43 dex |
| Rotational velocity (v sin i) | 23 km/s |
| Age | 146 Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is a chemically peculiar star and was first classified as a silicon star by American astronomer William Morgan in 1933. The stellar spectrum displays an overabundance of heavier elements; particularly silicon and gallium. These abundances may be caused by the magnetic field of the star, which produces concentrations of the observed elements in the outer atmosphere. It is an α² Canum Venaticorum-type variable star, ranging in magnitude from 5.15 down to 5.22. These variations are likely due to large spots or rings on the side of the star being observed.
The star and its companion orbit each other closely with a period of a week and an eccentricity of 0.18. The rotation period of the primary star has become locked to its orbit, so that one face is always pointed toward its companion. The abundance of gallium and silicon varies in a sinusoidal pattern that matches this period.
The primary has around 2.9 times the mass of the Sun, 3.5 times the Sun's radius, and is emitting 190 times the luminosity of the Sun. The effective temperature of the star's photosphere is 12,600 K, giving it the blue-white hue of a B-type star.