HD 32667 is a hierarchical triple star system located about 192 light-years (59 pc) away in the southern constellation of Lepus. The brightest of the three components, and the only one visible, is a hot white subgiant star. With an apparent magnitude of 5.582, it is faintly visible by the naked eye in dark skies. In Chinese astronomy, the star was given the name Jiǔ yóu zēng qī (Chinese: 九斿增七; lit. 'Nine flag addition seven'),[6] meaning it was the seventh star added to the asterism Jiǔ yóu (九斿, "Imperial Military Flag") in the Net mansion, when the star chart Yixiang Kaocheng (仪象考成) was compiled between 1744 and 1752.[7][8]
  | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Gemini |
| Right ascension | 05h 03m 53.27185s[1] |
| Declination | −24° 23′ 17.3310″[1] |
| Apparent magnitude (V) | 5.582[1] |
| Characteristics | |
| Spectral type | (A2IV[1] + unknown) + M |
| B−V color index | +0.100[1] |
| Astrometry | |
| Radial velocity (Rv) | 27.770 ± 1.200[1] km/s |
| Proper motion (μ) | RA: 24.991[1] mas/yr Dec.: -37.918[1] mas/yr |
| Parallax (π) | 16.9975 ± 0.0397 mas[1] |
| Distance | 191.9 ± 0.4 ly (58.8 ± 0.1 pc) |
| Orbit[2] | |
| Primary | HD 32667 Aa |
| Companion | HD 32667 Ab |
| Period (P) | ~4 or ~46 d |
| Eccentricity (e) | unknown, possibly ~0.8 |
| Orbit[2] | |
| Primary | HD 32667 A |
| Companion | HD 32667 B |
| Semi-major axis (a) | 0.5329±0.0013" (2808 AU[3]) |
| Inclination (i) | 71+24 −25° |
| Details | |
| HD 32667 Aa | |
| Mass | 2.1164 ± 0.0040[4] M☉ |
| Surface gravity (log g) | 4.1014 ± 0.0300[4] cgs |
| Temperature | 9198 ± 92[4] K |
| Metallicity [Fe/H] | 0.1853 ± 0.0300[4] dex |
| Rotational velocity (v sin i) | 117.17 ± 2.48[4] km/s |
| Age | 530+135 −140[2] Myr |
| HD 32667 Ab | |
| Mass | ≤1.44[2] M☉ |
| HD 32667 B | |
| Mass | 0.1053+0.0019 −0.0022,[2] 0.21[3] M☉ |
| Luminosity | 0.000933+0.000067 −0.000062[2] L☉ |
| Other designations | |
| Database references | |
| SIMBAD | HD 32667 |
The star is listed in the Catalogue of Ap, HgMn and Am Stars as an A2-type Am star designated Renson 8370,[5] although astronomer Dorrit Hoffleit suggested the contrary, classing it as an A3 weak-line star.[9]
Stellar companions
editHD 32667 Ab
editRadial velocity variations were reported as early as 1930,[10] indicating the existence of an unresolved companion (HD 1645 Ab) orbiting close to the primary star. The 1991 edition of the Bright Star Catalogue lists HD 32667 (HR 1645) as a spectroscopic binary. However, this secondary star would remain hardly studied, with existing measurements being of "very bad" quality.[2] In 2019, rough constraints were made on the nature of the secondary, namely that it does not weigh more than 1.44 M☉, has either a highly eccentric (e~0.8) 46-day orbit or a 4-day orbit with an indeterminate eccentricity, and that the magnitude difference with the brighter primary is substantial. Further research is needed to determine its precise characteristics.[2]
HD 32667 B
editA distant red dwarf companion revolving around the inner binary (Aa/Ab) was discovered in 2019 from data collected by the Gemini Planet Imager. The discovery paper described it as a 110.3 MJ (0.1053 M☉) ultra-cool dwarf with a spectral type of M8, located at a separation of 0.533" from the inner binary.[2] A 2023 study presented a semi-major axis of 2,808 AU (4.201×1011 km), a substantially higher mass of 0.21 M☉, and a spectral type of M4V.[3]
References
edit- ^ a b c d e f g h i j "HD 32667". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 8 August 2024.
- ^ a b c d e f g h i j De Rosa, Robert J.; et al. (1 December 2019). "Detection of a Low-mass Stellar Companion to the Accelerating A2IV Star HR 1645". The Astronomical Journal. 158 (6): 226. doi:10.3847/1538-3881/ab4ef7. ISSN 0004-6256.
- ^ a b c Waisberg, Idel; Klein, Ygal; Katz, Boaz (31 March 2023). "Binarity and beyond in A stars – I. Survey description and first results of VLTI/GRAVITY observations of VAST targets with high Gaia–Hipparcos accelerations". Monthly Notices of the Royal Astronomical Society. 521 (4): 5232–5254. doi:10.1093/mnras/stad872. ISSN 0035-8711.
- ^ a b c d e Borisov, Sviatoslav B.; Chilingarian, Igor V.; Rubtsov, Evgenii V.; Ledoux, Cédric; Melo, Claudio; Grishin, Kirill A.; Katkov, Ivan Yu.; Goradzhanov, Vladimir S.; Afanasiev, Anton V.; Kasparova, Anastasia V.; Saburova, Anna S. (1 May 2023). "New Generation Stellar Spectral Libraries in the Optical and Near-infrared. I. The Recalibrated UVES-POP Library for Stellar Population Synthesis*". The Astrophysical Journal Supplement Series. 266 (1): 11. doi:10.3847/1538-4365/acc321. ISSN 0067-0049. Retrieved 11 September 2024 – via vizier.cds.unistra.fr.
- ^ a b Renson, P.; Manfroid, J. (2009). "Catalogue of Ap, HgMn and Am stars". Astronomy & Astrophysics. 498 (3): 961–966. doi:10.1051/0004-6361/200810788. ISSN 0004-6361. Retrieved 11 September 2024 – via visier.cds.unistra.fr.
- ^ Yi, Shitong (April 1981). 中西对照恒星图表 [Atlas Comparing Chinese and Western Star Maps and Catalogues] (in Chinese). 科学出版社.
- ^ 乾嘉时期清廷的西方文化政策 [Western Cultural Policies of the Qing Court in the Qianjia Period]. lsqn.cn (in Chinese). 10 March 2007. Archived from the original on 7 July 2013. Retrieved 8 September 2024.
- ^ Auyang, Liang (30 August 2020). 星宿爭霸戰 [Battle of the Stars] (PDF). Taipei Skylight (in Chinese). Vol. 97. Taipei Astronomical Museum. pp. 22–27. ISSN 1727-0022. Retrieved 8 September 2024.
- ^ "VizieR Correlated Data from III/260/notes". Centre de données astronomiques de Strasbourg. Archived from the original on 11 September 2024. Retrieved 11 September 2024.
- ^ Neubauer, Ferdinand John (1930). "Radial velocities of 351 stars observed at the Chile station of the Lick Observatory in the period 1924 to 1929". Lick Observatory Bulletins. 15: 52. doi:10.5479/ADS/bib/1930LicOB.15.47N. ISSN 0075-9317.