HD 128294

HD 128294

Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Apus
Right ascension	14^h 41^m 59.70978^s[1]
Declination	−77° 00′ 41.2260″[1]
Apparent magnitude (V)	6.34±0.01[2]
Characteristics
Evolutionary stage	main sequence[1]
Spectral type	B9 III[3]
B−V color index	−0.027±0.002[4]
Astrometry
Radial velocity (Rv)	8.94±2.29[1] km/s
Proper motion (μ)	RA: −21.428 mas/yr[1] Dec.: −12.249 mas/yr[1]
Parallax (π)	5.2747 ± 0.0603 mas[1]
Distance	618 ± 7 ly (190 ± 2 pc)
Absolute magnitude (MV)	+0.07[4]
Details
Mass	2.66^+0.47 −0.25[5] M☉
Radius	3.62±0.11[5] R☉
Luminosity	145^+20 −31[1] L☉
Surface gravity (log g)	3.75^+0.09 −0.04[5] cgs
Temperature	10,336^+158 −296[5] K
Metallicity [Fe/H]	−0.09[6] dex
Age	286[7] Myr
Other designations
12 G. Apodis[8], CD−76°655, CPD−76°848, GC 19736, HD 128294, HIP 71870, SAO 257182[9]
Database references
SIMBAD	data

HD 128294 is a solitary, bluish-white hued star located in the southern circumpolar constellation Apus. It has an apparent magnitude of 6.34,[2] placing it near the limit for naked eye visibility, even under ideal conditions. Gaia DR3 parallax measurements imply a distance of 618 light-years.[1] At its current distance, HD 128294's brightness is heavily diminished by 0.43 magnitudes due to interstellar extinction[10] and it has an absolute magnitude of +0.07.[4]

HD 128294 has a stellar classification of B9 III,[3] indicating that it is an evolved blue giant. At the age of 286 million years,[7] the object has completed 71.9% of its main sequence lifetime according to Gaia DR3 models.[1] It has 2.66 times the mass of the Sun and a slightly enlarged radius 3.62 times that of the Sun's.[5] It radiates 145 times the luminosity of the Sun[1] from its photosphere at an effective temperature of 10,336 K.[5] According to astrophysical parameters based on the Gaia passband, HD 128294 has an iron abundance 81.3% that of the Sun's ([Fe/H) = −0.09),[6] making it slightly metal deficient.

References

1. 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. 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.
3. 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. Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331–346. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. eISSN 1562-6873. ISSN 1063-7737. S2CID 119257644.
5. 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.
6. 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.
7. Gontcharov, G. A. (November 2012). "Spatial distribution and kinematics of OB stars". Astronomy Letters. 38 (11): 694–706. arXiv:1606.09028. Bibcode:2012AstL...38..694G. doi:10.1134/S1063773712110035. eISSN 1562-6873. ISSN 1063-7737. S2CID 255202762.
8. 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.
9. "HD 128294". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved September 20, 2015.
10. Gontcharov, George A.; Mosenkov, Aleksandr V. (28 September 2017). "Verifying reddening and extinction for Gaia DR1 TGAS main sequence stars". Monthly Notices of the Royal Astronomical Society. 472 (4): 3805–3820. arXiv:1709.01160. Bibcode:2017MNRAS.472.3805G. doi:10.1093/mnras/stx2219. eISSN 1365-2966. ISSN 0035-8711. S2CID 118879856.