HD 167042 is a star with an orbiting exoplanet in the northern constellation of Draco. With an apparent visual magnitude of +5.97,[2] the star is dimly visible to the naked eye. It is located at a distance of 162 light years based on parallax measurements,[1] but it is drifting closer with a radial velocity of −18 km/s.[6] HD 164595 has a relatively large proper motion, traversing the celestial sphere at an angular rate of 0.270″ yr−1.[8]
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Draco |
| Right ascension | 18h 10m 31.640s[1] |
| Declination | +54° 17′ 11.59″[1] |
| Apparent magnitude (V) | +5.97[2] |
| Characteristics | |
| Evolutionary stage | subgiant[3] |
| Spectral type | K1 III.[4] or K1 IV[2] |
| U−B color index | +0.716[5] |
| B−V color index | +0.934[5] |
| Astrometry | |
| Radial velocity (Rv) | −17.88[6] km/s |
| Proper motion (μ) | RA: +107.630 mas/yr[1] Dec.: +247.345 mas/yr[1] |
| Parallax (π) | 20.1313 ± 0.0293 mas[1] |
| Distance | 162.0 ± 0.2 ly (49.67 ± 0.07 pc) |
| Absolute magnitude (MV) | 2.48[3] |
| Details[2] | |
| Mass | 1.88±0.07 M☉ |
| Radius | 5.70±0.10 R☉ |
| Luminosity | 12.47±0.54 L☉ |
| Surface gravity (log g) | 3.2±0.1 cgs |
| Temperature | 4,547±49 K |
| Metallicity [Fe/H] | −0.1 dex |
| Rotational velocity (v sin i) | 0.68[6] km/s |
| Age | 1.82±5.23 Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
The spectrum of HD 167042 presents as an evolved K-type giant star, an orange giant, with a stellar classification of K1 III.[4] However, the position of this star on the H-R diagram suggests it is still a subgiant star. When this star was a main sequence, it was white-hued mid to late A-type star based on its mass. It shows no significant magnetic activity in its chromosphere.[3] The star has 1.88 times the mass of the Sun and has expanded to 5.70 times the Sun's radius. It is radiating 12.5 times the luminosity of the Sun from its photosphere at an effective temperature of 4,547 K.[2]
Planetary system
editOn 28 November 2007, a preprint of the discovery of the exoplanet HD 167042 b was posted to the arXiv server. The peer reviewed paper was then published in The Astrophysical Journal on 1 March 2008.[3] The discovery was later independently confirmed.[9]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | >1.7 MJ | 1.30 | 412.6 ± 4 | 0.027 ± 0.04 | — | — |
See also
editReferences
edit- ^ a b c d e Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ a b c d e Ligi, R.; et al. (February 2016), "Radii, masses, and ages of 18 bright stars using interferometry and new estimations of exoplanetary parameters", Astronomy & Astrophysics, 586: 23, arXiv:1511.03197, Bibcode:2016A&A...586A..94L, doi:10.1051/0004-6361/201527054, S2CID 15941645, A94.
- ^ a b c d e Johnson, John Asher; et al. (2008). "Retired A Stars and Their Companions. II. Jovian Planets Orbiting κ CrB and HD 167042". The Astrophysical Journal. 675 (1): 784–789. arXiv:0711.4367. Bibcode:2008ApJ...675..784J. doi:10.1086/526453. S2CID 12367629.
- ^ a b Sharma, Kaushal; et al. (January 2020). "Application of convolutional neural networks for stellar spectral classification". Monthly Notices of the Royal Astronomical Society. 491 (2): 2280–2300. arXiv:1909.05459. Bibcode:2020MNRAS.491.2280S. doi:10.1093/mnras/stz3100.
- ^ a b Jennens, P. A.; Helfer, H. L. (September 1975), "A new photometric metal abundance and luminosity calibration for field G and K giants", Monthly Notices of the Royal Astronomical Society, 172 (3): 667–679, Bibcode:1975MNRAS.172..667J, doi:10.1093/mnras/172.3.667.
- ^ a b c Jofré, E.; et al. (2015), "Stellar parameters and chemical abundances of 223 evolved stars with and without planets", Astronomy & Astrophysics, 574: A50, arXiv:1410.6422, Bibcode:2015A&A...574A..50J, doi:10.1051/0004-6361/201424474, S2CID 53666931.
- ^ "HD 167042". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-08-12.
- ^ Lépine, Sébastien; Shara, Michael M. (March 2005). "A Catalog of Northern Stars with Annual Proper Motions Larger than 0.15" (LSPM-NORTH Catalog)". The Astronomical Journal. 129 (3): 1483–1522. arXiv:astro-ph/0412070. Bibcode:2005AJ....129.1483L. doi:10.1086/427854. S2CID 2603568.
- ^ Sato, Bun'ei; et al. (2008). "Planetary Companions to Evolved Intermediate-Mass Stars: 14 Andromedae, 81 Ceti, 6 Lyncis, and HD167042". Publications of the Astronomical Society of Japan. 60 (6): 1317–1326. arXiv:0807.0268. Bibcode:2008PASJ...60.1317S. doi:10.1093/pasj/60.6.1317. S2CID 67841762.
External links
edit- "Notes for star HD 167042". Extrasolar Planets Encyclopaedia. Archived from the original on November 6, 2007. Retrieved 2008-08-24.