HD 115404 is a binary star system located in the constellation Coma Berenices. Parallax measurements made by Hipparcos put the system at 36 light-years, or 11 parsecs, away.[12] The combined apparent magnitude of the system is 6.52,[11] with the magnitudes of the components being 6.66 and 9.50.[2]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Coma Berenices |
| HD 115404 A | |
| Right ascension | 13h 16m 51.051430s[1] |
| Declination | +17° 01′ 01.840901″[1] |
| Apparent magnitude (V) | 6.66[2] |
| HD 115404 B | |
| Right ascension | 13h 16m 51.554014s[3] |
| Declination | +17° 00′ 59.892133″[3] |
| Apparent magnitude (V) | 9.50[2] |
| Characteristics | |
| U−B color index | +0.64[4] |
| B−V color index | +0.92[4] |
| HD 115404 A | |
| Spectral type | K2 V[5] |
| HD 115404 B | |
| Spectral type | M0.5 V[6] |
| Astrometry | |
| HD 115404 A | |
| Radial velocity (Rv) | 7.62 ± 0.09[7] km/s |
| Proper motion (μ) | RA: 636.285±0.028 mas/yr[1] Dec.: −264.678±0.031 mas/yr[1] |
| Parallax (π) | 91.0176 ± 0.0236 mas[1] |
| Distance | 35.834 ± 0.009 ly (10.987 ± 0.003 pc) |
| HD 115404 B | |
| Radial velocity (Rv) | 5.95±0.13[3] km/s |
| Proper motion (μ) | RA: 649.666±0.031 mas/yr[3] Dec.: −263.937±0.026 mas/yr[3] |
| Parallax (π) | 90.9475 ± 0.0232 mas[3] |
| Distance | 35.862 ± 0.009 ly (10.995 ± 0.003 pc) |
| Orbit[8] | |
| Period (P) | 770.0 yr |
| Semi-major axis (a) | 8.06″ |
| Eccentricity (e) | 0.12 |
| Inclination (i) | 93.41° |
| Longitude of the node (Ω) | 104.66° |
| Periastron epoch (T) | B 1875.0 |
| Argument of periastron (ω) (secondary) | 276.99° |
| Details | |
| HD 115404 A | |
| Mass | 0.70 ± 0.09[9] M☉ |
| Radius | 0.76 ± 0.02[9] R☉ |
| Luminosity | 3.1[9] L☉ |
| Surface gravity (log g) | 4.58 ± 0.03[9] cgs |
| Temperature | 4976[9] K |
| Metallicity [Fe/H] | −0.08[9] dex |
| Rotational velocity (v sin i) | 2.8[9] km/s |
| Age | 10.2 (5.4–13.5)[9] Gyr |
| HD 115404 B | |
| Mass | 0.542[10] M☉ |
| Radius | 0.550[10] R☉ |
| Other designations | |
| Database references | |
| SIMBAD | A |
| B | |
| ARICNS | A |
| B | |
The primary component, designated A, is a K-type main sequence star.[5] It is about 70% as massive as the Sun, and is 0.76 times as wide.[9] Its companion is a red dwarf (M0.5 V).[6] It has 54.2% the mass of the Sun, and is 0.55 times as wide.[10] The two stars orbit each other every 770 years, and are separated by about 8″.[8] The system is thought to be fairly old, at 5.4 to 13.5 billion years old.[9]
In 2022, two exoplanets, Neptunian and super-Jovian in mass, were discovered in orbit around the primary star using a combination of radial velocity and astrometry.[13]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | ≥0.097+0.020 −0.022 MJ |
0.088+0.003 −0.004 |
10.5+0.001 −0.002 |
0.232+0.197 −0.138 |
— | — |
| c | 10.319+1.473 −1.209 MJ |
11.364+3.301 −1.905 |
15319.2+7240.3 −3526.2 |
0.211+0.173 −0.102 |
25.791+1.842 −2.157° |
— |
References
edit- ^ a b c d 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 Fabricius, C.; Høg, E.; Makarov, V. V.; Mason, B. D.; Wycoff, G. L.; Urban, S. E. (2002). "The Tycho double star catalogue". Astronomy and Astrophysics. 384: 180–189. Bibcode:2002A&A...384..180F. doi:10.1051/0004-6361:20011822.
- ^ 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 Cowley, A. P.; Hiltner, W. A.; Witt, A. N. (1967). "Spectral classification and photometry of high proper motion stars". The Astronomical Journal. 72: 1334. Bibcode:1967AJ.....72.1334C. doi:10.1086/110413.
- ^ a b White, Russel J.; Gabor, Jared M.; Hillenbrand, Lynne A. (2007). "High-Dispersion Optical Spectra of Nearby Stars Younger Than the Sun". The Astronomical Journal. 133 (6): 2524. arXiv:0706.0542. Bibcode:2007AJ....133.2524W. doi:10.1086/514336. S2CID 122854.
- ^ a b Alonso-Floriano, F. J.; Morales, J. C.; Caballero, J. A.; Montes, D.; Klutsch, A.; Mundt, R.; Cortés-Contreras, M.; Ribas, I.; Reiners, Ansgar; Amado, P. J.; Quirrenbach, A.; Jeffers, S. V. (2015). "CARMENES input catalogue of M dwarfs" (PDF). Astronomy & Astrophysics. 577: A128. arXiv:1502.07580. Bibcode:2015A&A...577A.128A. doi:10.1051/0004-6361/201525803. S2CID 53135130.[permanent dead link]
- ^ Maldonado, J.; Martínez-Arnáiz, R. M.; Eiroa, C.; Montes, D.; Montesinos, B. (2010). "A spectroscopy study of nearby late-type stars, possible members of stellar kinematic groups". Astronomy and Astrophysics. 521: A12. arXiv:1007.1132. Bibcode:2010A&A...521A..12M. doi:10.1051/0004-6361/201014948. S2CID 119209183.
- ^ a b "Sixth Catalog of Orbits of Visual Binary Stars". United States Naval Observatory. Archived from the original on 1 August 2017. Retrieved 11 August 2017.
- ^ a b c d e f g h i j Brewer, John M.; Fischer, Debra A.; Valenti, Jeff A.; Piskunov, Nikolai (2016). "Spectral Properties of Cool Stars: Extended Abundance Analysis of 1,617 Planet-Search Stars". The Astrophysical Journal Supplement Series. 225 (2): 32. arXiv:1606.07929. Bibcode:2016ApJS..225...32B. doi:10.3847/0067-0049/225/2/32. S2CID 118507965.
- ^ a b c Newton, Elisabeth R.; Irwin, Jonathan; Charbonneau, David; Berlind, Perry; Calkins, Michael L.; Mink, Jessica (2017). "The Hα emission of nearby M dwarfs and its relation to stellar rotation". The Astrophysical Journal. 834 (1): 85. arXiv:1611.03509. Bibcode:2017ApJ...834...85N. doi:10.3847/1538-4357/834/1/85. S2CID 55000202.
- ^ a b "HD 115404". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 11 August 2017.
- ^ van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600. Vizier catalog entry
- ^ a b Feng, Fabo; Butler, R. Paul; et al. (August 2022). "3D Selection of 167 Substellar Companions to Nearby Stars". The Astrophysical Journal Supplement Series. 262 (21): 21. arXiv:2208.12720. Bibcode:2022ApJS..262...21F. doi:10.3847/1538-4365/ac7e57. S2CID 251864022.