HD 123657
  | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Boötes |
| Right ascension | 14h 07m 55.755s[1] |
| Declination | 43° 51′ 16.03″[1] |
| Apparent magnitude (V) | 4.98–5.33[2][3] |
| Characteristics | |
| Evolutionary stage | AGB[4] |
| Spectral type | M4.5III[5] |
| U−B color index | 1.66[6] |
| B−V color index | 1.58[6] |
| R−I color index | 1.66[6] |
| Variable type | LB[5] |
| Astrometry | |
| Radial velocity (Rv) | −36.24[7] km/s |
| Proper motion (μ) | RA: +11.443 mas/yr[1] Dec.: −30.812 mas/yr[1] |
| Parallax (π) | 6.0110±0.1554 mas[1] |
| Distance | 540 ± 10 ly (166 ± 4 pc) |
| Absolute magnitude (MV) | −0.90[8] |
| Details | |
| Mass | 3.96[9] M☉ |
| Radius | 113[10] R☉ |
| Luminosity | 1,600±130[10] L☉ |
| Surface gravity (log g) | 0.66[11] cgs |
| Temperature | 3,444±125[10] K |
| Metallicity [Fe/H] | −0.03[12] dex |
| Other designations | |
| BY Boötis, HD 123657, HIP 69038, HR 5299, GSC 03040-00969, TYC 3040-969-1, BD+44°2325, IRAS 14059+4405, IRC +40253, SAO 44901 | |
| Database references | |
| SIMBAD | data |
HD 123657 (BY Boötis) is a star in the northern constellation of Boötes, near the end of the handle of the Big Dipper. It is a fifth-magnitude star, and can be spotted to the unaided eye in sufficiently dark skies, far from light pollution. Based on stellar parallax measurements, it is about 540 light-years distant.
This is a slow irregular variable with an apparent magnitude varying between 4.98 and 5.33.[2][3] The variability of the brightness of HD 123657 was announced by Joel Stebbins and Charles Morse Huffer in 1928, based on observations made at Washburn Observatory.[14] The star was given its variable star designation, BY Boötis, in 1973.[15]
HD 123657 has a spectral classification of M4.5III,[5] placing it as a cool red giant that exhausted its hydrogen supply. It has expanded to over 110 times the size of the Sun, now radiating 1,600 times its luminosity at a cool photosphere that has an effective temperature of 3,400 K.[10]
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 Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1. Bibcode:2009yCat....102025S.
- ^ a b "VSX : Detail for BY Boo". www.aavso.org. Retrieved 2025-03-11.
- ^ Alonso-Hernández, J.; Sánchez Contreras, C.; Sahai, R. (2024). "CO emission survey of asymptotic giant branch stars with ultraviolet excesses". Astronomy and Astrophysics. 684: A77. arXiv:2401.08546. Bibcode:2024A&A...684A..77A. doi:10.1051/0004-6361/202347317.
- ^ a b c Alvarez, R.; Jorissen, A.; Plez, B.; Gillet, D.; Fokin, A.; Dedecker, M. (2001). "Envelope tomography of long-period variable stars". Astronomy and Astrophysics. 379: 305–322. arXiv:astro-ph/0109259. Bibcode:2001A&A...379..305A. doi:10.1051/0004-6361:20011261. S2CID 15502307.
- ^ a b c Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues. 2237: 0. Bibcode:2002yCat.2237....0D.
- ^ Famaey, B.; Jorissen, A.; Luri, X.; Mayor, M.; Udry, S.; Dejonghe, H.; Turon, C. (2005). "Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters". Astronomy and Astrophysics. 430: 165. arXiv:astro-ph/0409579. Bibcode:2005A&A...430..165F. doi:10.1051/0004-6361:20041272. S2CID 17804304.
- ^ Park, Sunkyung; Kang, Wonseok; Lee, Jeong-Eun; Lee, Sang-Gak (2013). "Wilson-Bappu Effect: Extended to Surface Gravity". The Astronomical Journal. 146 (4): 73. arXiv:1307.0592. Bibcode:2013AJ....146...73P. doi:10.1088/0004-6256/146/4/73. S2CID 119187733.
- ^ Charbonnel, C.; Lagarde, N.; Jasniewicz, G.; North, P. L.; Shetrone, M.; Krugler Hollek, J.; Smith, V. V.; Smiljanic, R.; Palacios, A.; Ottoni, G. (2020). "Lithium in red giant stars: Constraining non-standard mixing with large surveys in the Gaia era". Astronomy and Astrophysics. 633: A34. arXiv:1910.12732. Bibcode:2020A&A...633A..34C. doi:10.1051/0004-6361/201936360.
- ^ a b c d McDonald, I.; Zijlstra, A. A.; Watson, R. A. (2017-10-01). "Fundamental parameters and infrared excesses of Tycho-Gaia stars". Monthly Notices of the Royal Astronomical Society. 471 (1): 770–791. arXiv:1706.02208. Bibcode:2017MNRAS.471..770M. doi:10.1093/mnras/stx1433. ISSN 0035-8711.
- ^ Coelho, Paula R. T.; Bruzual, Gustavo; Charlot, Stéphane (2020). "To use or not to use synthetic stellar spectra in population synthesis models?". Monthly Notices of the Royal Astronomical Society. 491 (2): 2025. arXiv:1910.11902. Bibcode:2020MNRAS.491.2025C. doi:10.1093/mnras/stz3023.
- ^ Marrese, P. M.; Boschi, F.; Munari, U. (2003). "High resolution spectroscopy over lambda lambda 8500-8750 Å for GAIA. IV. Extending the cool MK stars sample". Astronomy and Astrophysics. 406 (3): 995. Bibcode:2003A&A...406..995M. doi:10.1051/0004-6361:20030647.
- ^ "Hipparcos Tools Interactive Data Access". Hipparcos. ESA. Retrieved 8 December 2021.
- ^ Stebbins, Joel; Huffer, C. M. (1928). "The Constancy of the Light of Red Stars". Publications of the Washburn Observatory. 15: 137–174. Bibcode:1928PWasO..15..137S.
- ^ Kukarkin, B. V.; Kholopov, P. N.; Kukarkina, N. P.; Perova, N. B. (October 1973). "59th Name-List of Variable Stars" (PDF). Information Bulletin on Variable Stars. 834: 1–22. Bibcode:1973IBVS..834....1K. Retrieved 4 December 2024.
