| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Hercules |
| Right ascension | 17h 41m 58.632s [1] |
| Declination | +15° 57′ 08.76″ [1] |
| Apparent magnitude (V) | 5.54 [2] |
| Characteristics | |
| Evolutionary stage | Main sequence [3] |
| Spectral type | F4 Vw [4] |
| U−B color index | −0.05 [5] |
| B−V color index | +0.387±0.012 [2] |
| Astrometry | |
| Radial velocity (Rv) | −43.7 [6] km/s |
| Proper motion (μ) | RA: −1.868 mas/yr [1] Dec.: +101.120 mas/yr [1] |
| Parallax (π) | 28.5131±0.0532 mas [1] |
| Distance | 114.4 ± 0.2 ly (35.07 ± 0.07 pc) |
| Absolute magnitude (MV) | 2.74 [7] |
| Details | |
| HR 6594 A | |
| Mass | 1.34 [8] M☉ |
| Radius | 0.97 [9] R☉ |
| Luminosity | 6.17 [2] L☉ |
| Surface gravity (log g) | 4.07 [3] cgs |
| Temperature | 6,615 [3] K |
| Metallicity [Fe/H] | −0.04 [10] dex |
| Rotational velocity (v sin i) | 31.7 [3] km/s |
| Age | 1.2 [8] Gyr |
| Other designations | |
| BD−16° 3256, HD 160910, HIP 86623, HR 6594, SAO 103033 [11] | |
| Database references | |
| SIMBAD | data |
HR 6594 is the Bright Star Catalogue designation for a binary star [12] system in the northern constellation of Hercules. It is faintly visible to the naked eye with an apparent visual magnitude of 5.54; [2] according to the Bortle scale, it is sufficiently bright to be visible from dark suburban skies. The distance to this system, as determined using parallax measurements, [1] is about 114 light years. It is drifting closer with a heliocentric radial velocity of −43.7 km/s, [6] and is predicted to come as near as 47 light-years in 686,000 years. [2] On the celestial sphere it is located near the star Alpha Ophiuchi; their projected separation is just 3 light years, although their actual separation is much greater. [13]
The primary is an F-type main sequence star with a stellar classification of F4 Vw, where the w indicates relatively weak metallic features in the ultraviolet spectrum. [4] This star has 134% of the Sun's mass, [8] but only 97% of the solar radius. [9] It is spinning with a projected rotational velocity of 31.7 km/s, [3] and is around 1.2 billion years old. [8] The effective temperature of the outer atmosphere is 6,615 K, [3] giving it the yellow-white hue of an F-type star. [14] The abundance of elements other than hydrogen or helium, what astronomers term the metallicity, is similar to that in the Sun. [10]
It has a magnitude 9.38 companion star orbiting with a 144-year period, a semimajor axis spanning 1.04 arcseconds, and an eccentricity of 0.42. [12] There is a third, visual companion of magnitude 14.46 at an angular separation of 154.70 arcseconds along a position angle of 271°, as of 2001. [15]