HD 124099

HD 124099
Location of HD 124099 on the map (circled)
Observation data
Epoch J2000.0      Equinox ICRS
Constellation Apus
Right ascension 14h 16m 55.14838s
Declination −77° 39′ 51.1971″
Apparent magnitude (V) 6.46 - 6.49
Characteristics
Spectral type K2 IIp
U−B color index +1.33
B−V color index +1.42
Variable type SRD:
Astrometry
Radial velocity (Rv)−10.2±0.4 km/s
Proper motion (μ) RA: −4.602 mas/yr
Dec.: −3.712 mas/yr
Parallax (π)1.6098±0.0195 mas
Distance2,030 ± 20 ly
(621 ± 8 pc)
Absolute magnitude (MV)−2.10
Details
Mass4.22 M☉
Radius71.4+3.2
−13.5 or 99.4±2.4 R☉
Luminosity1,545±46 or 2,926+74
−75 L☉
Surface gravity (log g)1.29 cgs
Temperature4,426±122 K
Metallicity [Fe/H]−0.21 dex
Rotational velocity (v sin i)5.6±2.0 km/s
Other designations
7 G. Apodis, NSV 20066, CD−77°643, CPD−77°940, GC 19200, HD 124099, HIP 69778, HR 5306, SAO 257131
Database references
SIMBADdata

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 apparent magnitude of 6.4, 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, but it is drifting closer with a heliocentric radial velocity of −10.2 km/s. At its current distance, HD 124099's average brightness is diminished by 0.47 magnitudes due to interstellar extinction and it has an absolute magnitude of −2.10.

A light curve for HD 124099, plotted from Hipparcos data

HD 124099 has a stellar classification of K2 IIp, 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 but it has expanded to 71.4 times the radius of the Sun. It radiates 1,545 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,426 K. However, Gaia DR3 stellar evolution models give a larger radius of 99.4 R☉ and a higher luminosity of 2,926 L☉. HD 124099 is metal deficient with an iron abundance 61.2% that of the Sun's ([Fe/H] = −0.21) and it spins modestly with a projected rotational velocity of 5.6 km/s. 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.

References

  1. 1 2 3 4 5 6 7 8 9 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.
  2. 1 2 3 4 "VSX : Detail for NSV 20066". www.aavso.org. Retrieved 31 July 2023.
  3. 1 2 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.
  4. ↑ 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.
  5. ↑ 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.
  6. 1 2 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.
  7. 1 2 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.
  8. 1 2 3 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.
  9. 1 2 3 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.
  10. 1 2 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.
  11. 1 2 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.
  12. 1 2 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.
  13. ↑ 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.
  14. ↑ SIMBAD, HD 124099 (accessed 20 September 2015)
  15. ↑ 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.
  16. ↑ EAS (1997). "The HIPPARCOS and TYCHO catalogues". Astrometric and Photometric Star Catalogues Derived from the ESA Hipparcos Space Astrometry Mission. ESA SP Series. 1200. Noordwijk, Netherlands: ESA Publications Division. Bibcode:1997ESASP1200.....E. ISBN 9290923997. Retrieved 15 October 2022.{{cite journal}}: CS1 maint: periodical has ISBN (link)