Syrma
 Location of ι Virginis. |
|
| Observation data Epoch J2000 Equinox J2000 |
|
|---|---|
| Constellation | Virgo |
| Right ascension | 14h 16m 00.86951s |
| Declination | −06° 00′ 01.9633″ |
| Apparent magnitude (V) | 4.08 |
| Characteristics | |
| Spectral type | F7IV-V |
| U−B color index | +0.02 |
| B−V color index | +0.52 |
| Astrometry | |
| Radial velocity (Rv) | 12.51 ± 0.18 km/s |
| Proper motion (μ) |
RA: -26.31 mas/yr Dec.: -419.38 mas/yr |
| Parallax (π) | 44.97 ± 0.19mas |
| Distance | 72.5 ± 0.3 ly (22.24 ± 0.09 pc) |
| Absolute magnitude (MV) | 2.4 |
| Orbit | |
| Period (P) | 55 yr |
| Semi-major axis (a) | 0.830 ± 0.020″ |
| Eccentricity (e) | 0.1 ± 0.2 |
| Inclination (i) | 60 ± 9° |
| Longitude of the node (Ω) | 3 ± 20° |
| Periastron epoch (T) | 1950.7 ± 2.7 |
|
Argument of periastron (ω) (secondary) |
336 ± 27° |
| Details | |
| ι Vir A | |
| Mass | 1.5 ± 0.05 M☉ |
| Radius | 2.5 R☉ |
| Luminosity | 8.7 L☉ |
| Surface gravity (log g) | 3.94 cgs |
| Temperature | 6282 K |
| Metallicity [Fe/H] | −0.11 dex |
| Rotational velocity (v sin i) | 16 km/s |
| ι Vir B | |
| Mass | 0.6 ± 0.2 M☉ |
| Other designations | |
| Database references | |
| SIMBAD | data |
Iota Virginis (ι Virginis, abbreviated Iota Vir, ι Vir), also named Syrma, is a binary star in the constellation of Virgo. Its apparent magnitude is 4.08. Based on its parallax, it is assumed to be relatively nearby, at 72.5 light-years (22.24 parsecs).
ι Virginis (Latinised to Iota Virginis) is the star's Bayer designation.
It bore the traditional name Syrma, derived from the Arabic سرما (تطريز sirmā "train (of a garment)". In 2016, the International Astronomical Union organized a Working Group on Star Names (WGSN) to catalogue and standardize proper names for stars. The WGSN approved the name Syrma for this star on 12 September 2016 and it is now so entered in the IAU Catalog of Star Names.
In China, 亢宿 (Kàng Xiù), meaning Neck, refers to an asterism consisting of this star, Kappa Virginis, Phi Virginis and Lambda Virginis. Consequently, Iota Virginis itself is known as 亢宿二 (Kàngsuèr, English: the Second Star of Neck.)
Iota Virginis is a yellow-colored star with a spectral class of F7IV-V. This star has 1.5 times the mass of the Sun, with a projected rotational velocity of 16 km s−1. It is radiating 8.7 times the luminosity of the Sun from its outer atmosphere at an effective temperature of 6,282 K. The radius is about 2.5 times that of the Sun.
...
Wikipedia