HD 124099 (HR 5306; NSV 20066; 7 G. Apodis) is a solitary orange-hued star located in the southern circumpolar constellation Apus. It has an average apparent magnitude of 6.47,[2] placing it very close to the limit for naked eye visibility, even under ideal conditions. The object is located relatively far at a distance of approximately 2,030 light-years based on Gaia DR3 parallax measurements,[1] but it is drifting closer with a heliocentric radial velocity of −10.2 km/s.[7] At its current distance, HD 124099's average brightness is diminished by 0.47 magnitudes due to interstellar extinction[16] and it has an absolute magnitude of −2.10.[8]
Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
---|---|
Constellation | Apus |
Right ascension | 14h 16m 55.14838s[1] |
Declination | −77° 39′ 51.1971″[1] |
Apparent magnitude (V) | 6.47[2] (6.46 - 6.49)[3] |
Characteristics | |
Spectral type | K2 IIp[4] |
U−B color index | +1.33[5] |
B−V color index | +1.42[6] |
Variable type | SRD:[3] |
Astrometry | |
Radial velocity (Rv) | −10.2±0.4[7] km/s |
Proper motion (μ) | RA: −4.602 mas/yr[1] Dec.: −3.712 mas/yr[1] |
Parallax (π) | 1.6098 ± 0.0195 mas[1] |
Distance | 2,030 ± 20 ly (621 ± 8 pc) |
Absolute magnitude (MV) | −2.10[8] |
Details | |
Mass | 4.22[9] M☉ |
Radius | 71.4+3.2 −13.5[10] or 99.4±2.4[1] R☉ |
Luminosity | 1,545±46[10] or 2,926+74 −75[1] L☉ |
Surface gravity (log g) | 1.29[9] cgs |
Temperature | 4,426±122[11] K |
Metallicity [Fe/H] | −0.21[12] dex |
Rotational velocity (v sin i) | 5.6±2.0[13] km/s |
Other designations | |
Database references | |
SIMBAD | data |
HD 124099 has a stellar classification of K2 IIp,[4] indicating that it is an evolved K-type bright giant with peculiarities in its spectrum; the peculiarity being that it has either a very weak or no G-band in its spectrum. It has 4.22 times the mass of the Sun[9] but it has expanded to 71.4 times the radius of the Sun.[10] It radiates 1,545 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,426 K.[11] However, Gaia DR3 stellar evolution models give a larger radius of 99.4 R☉ and a higher luminosity of 2,926 L☉.[1] HD 124099 is metal deficient with an iron abundance 61.2% that of the Sun's ([Fe/H] = −0.21)[12] and it spins modestly with a projected rotational velocity of 5.6 km/s.[13] The star is suspected to be a semiregular variable of the SRD subtype and it ranges from 6.46 to 6.49 within 528 days.[3]
References
edit- ^ a b c d e f g h 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 Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (March 2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27–L30. Bibcode:2000A&A...355L..27H. ISSN 0004-6361. S2CID 17128864.
- ^ a b c d "VSX : Detail for NSV 20066". www.aavso.org. Retrieved 31 July 2023.
- ^ a b Houk, N.; Cowley, A. P. (1975). University of Michigan Catalogue of two-dimensional spectral types for the HD stars: Declinations −90° to −53°. Vol. 1. Bibcode:1975mcts.book.....H.
- ^ Stagg, Christopher (1983). "The southern Be star photometric campaign - A first report". Hvar Observatory Bulletin. 7 (1): 143–146. Bibcode:1983HvaOB...7..143S. ISSN 0351-2657.
- ^ Cousins, A. W. J.; Stoy, R. H. (1962). "Photoelectric magnitudes and colours of Southern stars". Royal Greenwich Observatory Bulletins. 64: 103. Bibcode:1962RGOB...64..103C. S2CID 118805499.
- ^ a b Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35,495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. eISSN 1562-6873. ISSN 1063-7737. S2CID 119231169.
- ^ a b Corbally, C. J.; Garrison, R. F. (1984). "Which Map of Absolute Magnitudes: Keenan or Schmidt-Kaler?". The Mk Process and Stellar Classification: 277. Bibcode:1984mpsc.conf..277C.
- ^ a b c Anders, F.; et al. (February 2022). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia EDR3 stars brighter than G = 18.5". Astronomy & Astrophysics. 658: A91. arXiv:2111.01860. Bibcode:2022A&A...658A..91A. doi:10.1051/0004-6361/202142369. eISSN 1432-0746. ISSN 0004-6361.
- ^ a b c Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b Stassun, Keivan G.; et al. (9 September 2019). "The Revised TESS Input Catalog and Candidate Target List". The Astronomical Journal. 158 (4): 138. arXiv:1905.10694. Bibcode:2019AJ....158..138S. doi:10.3847/1538-3881/ab3467. eISSN 1538-3881. hdl:1721.1/124721. S2CID 166227927.
- ^ a b Poggio, E.; Recio-Blanco, A.; Palicio, P. A.; Re Fiorentin, P.; de Laverny, P.; Drimmel, R.; Kordopatis, G.; Lattanzi, M. G.; Schultheis, M.; Spagna, A.; Spitoni, E. (30 September 2022). "The chemical signature of the Galactic spiral arms revealed by Gaia DR3". Astronomy & Astrophysics. 666: L4. arXiv:2206.14849. Bibcode:2022A&A...666L...4P. doi:10.1051/0004-6361/202244361. eISSN 1432-0746. ISSN 0004-6361.
- ^ a b De Medeiros, J. R.; Alves, S.; Udry, S.; Andersen, J.; Nordström, B.; Mayor, M. (January 2014). "A catalog of rotational and radial velocities for evolved stars V: Southern stars *". Astronomy & Astrophysics. 561: A126. arXiv:1312.3474. Bibcode:2014A&A...561A.126D. doi:10.1051/0004-6361/201220762. eISSN 1432-0746. ISSN 0004-6361. S2CID 54046583.
- ^ Gould, Benjamin Apthorp (1878). "Uranometria Argentina : brillantez y posicion de las estrellas fijas, hasta la septima magnitud, comprendidas dentro de cien grados del polo austral : con atlas". Resultados del Observatorio Nacional Argentino. 1. Bibcode:1879RNAO....1.....G.
- ^ SIMBAD, HD 124099 (accessed 20 September 2015)
- ^ Guarinos, J. (February 1995). "VizieR Online Data Catalog: Interstellar matter in the Galactic Disk (Guarinos J., 1992)". VizieR Online Data Catalog: 301V/86. Bibcode:1995yCat.5086....0G.