89 Herculis
From Infogalactic: the planetary knowledge core
| Observation data Epoch J2000 Equinox J2000 |
|
|---|---|
| Constellation | Hercules |
| Right ascension | 17h 55m 25.18892s[1] |
| Declination | 26° 02′ 59.9738″[1] |
| Apparent magnitude (V) | 5.36[2] (5.34 - 5.54[3]) |
| Characteristics | |
| Evolutionary stage | post-AGB |
| Spectral type | F2Ibe[4] |
| U−B color index | −0.34[2] |
| B−V color index | +0.34[2] |
| Variable type | SRd[3] |
| Astrometry | |
| Radial velocity (Rv) | −28.5[5] km/s |
| Proper motion (μ) | RA: 4.34[1] mas/yr Dec.: 5.89[1] mas/yr |
| Parallax (π) | 0.76 ± 0.23[1] mas |
| Distance | approx. 4,000 ly (approx. 1,300 pc) |
| Absolute magnitude (MV) | −6.5[6] |
| Details | |
| Mass | 1.0[7] M☉ |
| Radius | 71.0[7] R☉ |
| Luminosity | 8,350[7] L☉ |
| Surface gravity (log g) | 0.55[4] cgs |
| Temperature | 6,550[4] K |
| Metallicity | −0.5[4] |
| Rotational velocity (v sin i) | 23[8] km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
89 Herculis is a fifth-magnitude star in the constellation Hercules. Located about 4,000 light years away, it is among a rare class of post-AGB stars - low mass stars in the last stages of their lives, highly inflated to appear as supergiants.[4]
89 Her is a spectroscopic binary system with the pair surrounded by a dusty disc. The system shows variable brightness and spectral line profiles.[9] The companion has a very low mass and luminosity and orbits the primary in 288 days.[4]
89 Her is classified as a semiregular variable star, V441 Her, varying from magnitude 5.3 to 5.5 in around 68 days.[3]
References
- ↑ 1.0 1.1 1.2 1.3 1.4 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 2.0 2.1 2.2 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 3.0 3.1 3.2 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 4.0 4.1 4.2 4.3 4.4 4.5 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ 7.0 7.1 7.2 Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
- ↑ Lua error in package.lua at line 80: module 'strict' not found.
External links
- Jim Kaler's Stars, University of Illinois: 89 HER (89 Herculis)
