HD 109271
HD 109271 is a star in the constellation of Virgo. With an apparent magnitude of 8.05,[2] it cannot be seen with the naked eye. Parallax measurements made by Gaia put the star at a distance of 182 light-years (56.0 parsecs) away.[1]
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Virgo |
| Right ascension | 12h 33m 35.5543s[1] |
| Declination | −11° 37′ 18.7272″[1] |
| Apparent magnitude (V) | 8.05 ± 0.01[2] |
| Characteristics | |
| Spectral type | G5 V[2] |
| B−V color index | +0.658 ± 0.002[2] |
| Astrometry | |
| Radial velocity (Rv) | −5.10 ± 0.3[3] km/s |
| Proper motion (μ) | RA: −169.693±0.114[1] mas/yr Dec.: 80.882±0.108[1] mas/yr |
| Parallax (π) | 17.8697 ± 0.0660[1] mas |
| Distance | 182.5 ± 0.7 ly (56.0 ± 0.2 pc) |
| Absolute magnitude (MV) | 4.1 ± 0.1[2] |
| Details[2] | |
| Mass | 1.047 ± 0.024 M☉ |
| Luminosity | 2.0 ± 0.3 L☉ |
| Surface gravity (log g) | 4.28 ± 0.10 cgs |
| Temperature | 5783 ± 62 K |
| Metallicity [Fe/H] | 0.10 ± 0.05 dex |
| Rotational velocity (v sin i) | 2.7 km/s |
| Age | 7.3 ± 1.2 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
| Extrasolar Planets Encyclopaedia | data |
HD 109271 is a typical G-type main-sequence star. It has a mass of 1.047 M☉, but is twice as luminous as the Sun. It is also much older, at an age of 7.3 billion years.[2]
In 2020, a red dwarf companion of 0.6M☉ was found orbiting HD 109271 at projected separation 304 AU.[4]
Planetary system
From 2003 to 2012, the star was under observance from the High Accuracy Radial Velocity Planet Searcher (HARPS).[2]
In 2012, two eccentric hot Neptune-mass planets were deduced by radial velocity. They were published in January 2013. These are close to a 1:4 resonance. The system is like HD 69830.
A third Neptune in the Venus zone was hypothesised from the data.
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | >0.054 ± 0.004 MJ | 0.079 ± 0.001 | 7.8543 ± 0.0009 | 0.25 ± 0.08 | — | — |
| c | >0.076 ± 0.007 MJ | 0.196 ± 0.003 | 30.93 ± 0.02 | 0.15 ± 0.09 | — | — |
| d (unconfirmed) | >1.3 neptune MJ | 1 | 430 | 0.36 | — | — |
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.
- G. Lo Curto; et al. (2013). "The HARPS search for southern extrasolar planets: XXXVI. New multi-planet systems in the HARPS volume limited sample: a super-Earth and a Neptune in the habitable zone". Astronomy & Astrophysics. 551: A59. arXiv:1301.2741. Bibcode:2013A&A...551A..59L. doi:10.1051/0004-6361/201220415. S2CID 116916728.
- Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID 119231169.
- Ginski, Christian; Mugrauer, Markus; Adam, Christian; Vogt, Nikolaus; Rob van Holstein (2020), How many suns are in the sky? A SPHERE multiplicity survey of exoplanet host stars I, arXiv:2009.10363
- "Planet HD 109271 b". The Extrasolar Planets Encyclopaedia. Retrieved 3 September 2017.