HD 191760
HD 191760 is a star in the southern constellation of Telescopium. It has a yellow hue but is too dim to be visible to the naked eye with an apparent visual magnitude of 8.26.[2] The star is located at a distance of approximately 296 light years from the Sun based on parallax,[1] but is drifting closer with a radial velocity of −30 km/s.[2]
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Telescopium |
| Right ascension | 20h 13m 26.74533s[1] |
| Declination | −46° 12′ 03.7022″[1] |
| Apparent magnitude (V) | 8.26[2] |
| Characteristics | |
| Evolutionary stage | Subgiant[3] |
| Spectral type | G3IV/V[3] |
| B−V color index | 0.668±0.014[2] |
| Variable type | Constant[4] |
| Astrometry | |
| Radial velocity (Rv) | −30.1±0.4[2] km/s |
| Proper motion (μ) | RA: −0.083[1] mas/yr Dec.: −62.441[1] mas/yr |
| Parallax (π) | 11.0177 ± 0.1526[1] mas |
| Distance | 296 ± 4 ly (91 ± 1 pc) |
| Absolute magnitude (MV) | 3.71[2] |
| Details[3] | |
| Mass | 1.28+0.02 −0.10 M☉ |
| Radius | 1.62±0.07 R☉ |
| Luminosity | 2.69±0.20 L☉ |
| Surface gravity (log g) | 4.13+0.05 −0.04 cgs |
| Temperature | 5,794±76 K |
| Metallicity [Fe/H] | 0.29±0.07 dex |
| Rotation | 25.2 or 35.1 |
| Rotational velocity (v sin i) | 2.33±0.05 km/s |
| Age | 4.1+0.8 −2.8 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
The stellar classification of G3IV/V is consistent with a star that is evolving onto the subgiant branch, having exhausted the supply of hydrogen at its core. It is roughly four billion years old with a modest projected rotational velocity of 2.3 km/s. The star is 28% more massive than the Sun and 62% as large. The metallicity, or abundance of heavier elements, is higher than in the Sun. The star is radiating 2.7 times the luminosity of the Sun from its photosphere at an effective temperature of 5,794 K.[3]
Using the ESO HARPS instrument, in 2009 it was found to have a brown dwarf at least 38 times as massive as Jupiter orbiting at an average distance of 1.35 AU in a period of 506 days. This is an unusual distance from the star that has been termed the 'brown dwarf desert'.[3] The upper limit on the mass of this object is 28% of the mass of the Sun (0.28 M☉).[6]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| B | ≥38.17±1.02 MJ | 1.35 | 505.65±0.42 | 0.63±0.01 | — | — |
References
- Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. S2CID 119257644.
- Jenkins, J. S.; et al. (September 2009). "First Results From the Calan–Hertfordshire Extrasolar Planet Search: Exoplanets and the Discovery of an Eccentric Brown Dwarf in the Desert". Monthly Notices of the Royal Astronomical Society. 398 (2): 911–17. arXiv:0905.2985. Bibcode:2009MNRAS.398..911J. doi:10.1111/j.1365-2966.2009.15097.x.
- Paunzen, E.; et al. (January 1995). "Detection of Variability in HD191850". Information Bulletin on Variable Stars. 4151: 1. Bibcode:1995IBVS.4151....1P.
- "HD 191760". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-12-12.
- Sahlmann, J.; et al. (January 2011). "Search for brown-dwarf companions of stars". Astronomy and Astrophysics. 525: 24. arXiv:1009.5991. Bibcode:2011A&A...525A..95S. doi:10.1051/0004-6361/201015427. A95.