Astronomy:HD 1690
| Observation data Epoch J2000.0 Equinox (celestial coordinates) | |
|---|---|
| Constellation | Cetus |
| Right ascension | 00h 21m 13.327s[1] |
| Declination | −08° 16′ 52.16″[1] |
| Apparent magnitude (V) | 9.19[2] |
| Characteristics | |
| Evolutionary stage | Giant |
| Spectral type | K1 III[3] |
| B−V color index | 1.354±0.045[2] |
| Astrometry | |
| Radial velocity (Rv) | +18.216±0.011[4] km/s |
| Proper motion (μ) | RA: 13.285[1] mas/yr Dec.: 2.919[1] mas/yr |
| Parallax (π) | 1.2679 ± 0.0273[1] mas |
| Distance | 2,570 ± 60 ly (790 ± 20 pc) |
| Details | |
| Mass | 1.18±0.23[5] M☉ |
| Radius | 16.7[6] R☉ |
| Surface gravity (log g) | 2.12±0.17[5] cgs |
| Temperature | 4,393±85 K |
| Metallicity [Fe/H] | −0.32±0.06 dex |
| Rotational velocity (v sin i) | 1.86±0.07 km/s |
| Age | 6.7±3.2[7] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
| Extrasolar Planets Encyclopaedia | data |
HD 1690 is a giant star with an orbiting exoplanet companion in the constellation of Cetus. It has an apparent visual magnitude of 9.19,[2] which is too faint to be visible to the naked eye. The distance to this system is approximately 2,570 light years, and it is drifting further away with a radial velocity of +18.2 km/s.[4] HD 1690 has no known companion star, making it a single star system.[9]
This is an evolved K-type giant star with a stellar classification of K1 III.[3] It has 1.18 times the mass of the Sun and, at the estimated age of 6.7 billion years (two billion years older than the Sun), it has expanded to 16 times the Sun's radius. The surface metallicity of HD 1690 (the abundance of elements more massive than helium) is 30% that of the sun.[5] The Hipparcos parallax data have resulted in a distance determination of just 1,012 light years,[10] but more recent data from Gaia data have placed HD 1690 much farther from the Sun at 2,500 light years.[11]
Planetary system
In 2010, a team of astronomers led by astronomer C. Moutou of the High Accuracy Radial Velocity Planet Searcher performed a radial-velocity analysis that detected a gas giant planet in orbit around HD 1690.[7]
The planet HD 1690 b has a very eccentric (far from circular) orbit; its orbital eccentricity is 0.64. This eccentricity suggests that its mass is at least six times that of Jupiter, classifying it as a super-Jupiter.[7] Other planets in the HD 1690 system are unlikely unless they are located on unstable crossing orbital paths.[9]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | >6.9±0.9 MJ | 1.3±0.02 | 533±1.7 | 0.64±0.04 | — | — |
References
- ↑ 1.0 1.1 1.2 1.3 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940 Gaia DR3 record for this source at VizieR.
- ↑ 2.0 2.1 2.2 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode: 2012AstL...38..331A.
- ↑ 3.0 3.1 Gray, R. O. et al. (2003). "Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 Parsecs: The Northern Sample. I". The Astronomical Journal 126 (4): 2048–2059. doi:10.1086/378365. Bibcode: 2003AJ....126.2048G.
- ↑ 4.0 4.1 Soubiran, C. et al. (2018). "Gaia Data Release 2. The catalogue of radial velocity standard stars". Astronomy and Astrophysics 616: A7. doi:10.1051/0004-6361/201832795. Bibcode: 2018A&A...616A...7S.
- ↑ 5.0 5.1 5.2 Mortier, A.; Santos, N. C.; Sousa, S. G.; Adibekyan, V. Zh.; Delgado Mena, E.; Tsantaki, M/; Israelian, G.; Mayor, M. (2013). "New and updated stellar parameters for 71 evolved planet hosts. On the metallicity - giant planet connection". Astronomy and Astrophysics 557 (A70): A70. doi:10.1051/0004-6361/201321641. Bibcode: 2013A&A...557A..70M.
- ↑ Zoghbi, J. A. (2011). "Quantization of Planetary Systems and its Dependency on Stellar Rotation". Publications of the Astronomical Society of Australia 28 (3): 177–201. doi:10.1071/AS09062. Bibcode: 2011PASA...28..177Z.
- ↑ 7.0 7.1 7.2 Moutou, Claire; Mayor, Michel; Lo Curto, Gaspare; Ségransan, Damien; Udry, Stéphane; Bouchy, François; Benz, Willy; Lovis, Christophe et al. (2010), The HARPS search for southern extra-solar planets: XXVI: Seven new planetary systems, doi:10.1051/0004-6361/201015371
- ↑ HD 1690, entry, SIMBAD. Accessed online June 22, 2020.
- ↑ 9.0 9.1 Wittenmyer, R. A.; Wang, S.; Horner, J.; Tinney, C. G.; Butler, R. P.; Jones, H. R. A.; O'Toole, S. J.; Bailey, J. et al. (2013). "Forever alone? Testing single eccentric planetary systems for multiple companions". The Astrophysical Journal Supplement Series 208 (1): 2. doi:10.1088/0067-0049/208/1/2. Bibcode: 2013ApJS..208....2W.
- ↑ van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. doi:10.1051/0004-6361:20078357. Bibcode: 2007A&A...474..653V.
- ↑ GaiaSource-2429846549069734784-2430330987021111936.csv line 6978
- ↑ Planet HD 1690 b on exoplanet.eu
Coordinates: 
00h 21m 13.3272s, −08° 16′ 52.1674″
 |  |
