HD 106248, also known as HR 4649, is a solitary, orange hued star located in the southern circumpolar constellation Chamaeleon. It has an apparent magnitude of 6.34,[2] placing it near the limit for naked eye visibility. Based on parallax measurements from Gaia DR3, the object is estimated to be 358 light years away from the Solar System.[1] It appears to be receding with a heliocentric radial velocity of 34.5 km/s.[5] At its current distance, HD 106248's brightness is diminished by 0.32 due to interstellar dust and Eggen (1993) lists it as a member of the old (thick) disk population.[14]

HD 106248
Location of HD 106248 on the map (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Chamaeleon
Right ascension 12h 13m 56.46291s[1]
Declination −78° 34′ 26.1715″[1]
Apparent magnitude (V) 6.34±0.01[2]
Characteristics
Spectral type K2/3 III CNII[3]
U−B color index +1.41[4]
B−V color index +1.21[4]
Astrometry
Radial velocity (Rv)34.5±0.4[5] km/s
Proper motion (μ) RA: −4.318 mas/yr[1]
Dec.: −20.594 mas/yr[1]
Parallax (π)9.1183 ± 0.0194 mas[1]
Distance357.7 ± 0.8 ly
(109.7 ± 0.2 pc)
Absolute magnitude (MV)+1.10[6]
Details
Mass1.19±0.82[7] M
Radius10.93[8] R
Luminosity49+2.3
−2.2
[7] L
Surface gravity (log g)2.42[9] cgs
Temperature4,700±122[10] K
Metallicity [Fe/H]+0.05[9] dex
Rotational velocity (v sin i)<1.5[11] km/s
Age4.31+0.75
−0.48
[1] Gyr
Other designations
39 G. Chamaeleontis[12], CD−77°542, CPD−77°804, GC 16698, HD 106248, HIP 59647, HR 4649, SAO 256915[13]
Database references
SIMBADdata

This is an evolved red giant with a stellar classification of K2/3 III CNII[3]—intermediate between a K2 and K3 giant star. The CNII suffix indicates that it has a strong overabundance of cyano radicals in its spectrum, making it a CN star.[15] It has 119% the mass of the Sun[7] and is estimated to be 4.31 billion years old,[1] slightly younger than the Sun. However, HD 106248 has already left the main sequence and has an enlarged radius of 10.9 R.[8] It radiates 49 times the luminosity of the Sun from its photosphere[7] at an effective temperature of 4,700 K.[10] The star has a solar metallicity and spins slowly with a projected rotational velocity lower than 1.5 km/s.[11]

References

edit
  1. ^ a b c d e f g 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. ^ 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.
  3. ^ a b Houk, N.; Cowley, A. P. (1975). University of Michigan Catalogue of two-dimensional spectral types for the HD stars. Volume I. Declinations −90° to −53°. Bibcode:1975mcts.book.....H.
  4. ^ a b Johnson, H. L.; Mitchell, R. I.; Iriarte, B.; Wisniewski, W. Z. (1966). "UBVRIJKL Photometry of the Bright Stars". Communications of the Lunar and Planetary Laboratory. 4: 99–110. Bibcode:1966CoLPL...4...99J.
  5. ^ 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.
  6. ^ 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.
  7. ^ a b c d Charbonnel, C.; Lagarde, N.; Jasniewicz, G.; North, P. L.; Shetrone, M.; Krugler Hollek, J.; Smith, V. V.; Smiljanic, R.; Palacios, A.; Ottoni, G. (January 2020). "Lithium in red giant stars: Constraining non-standard mixing with large surveys in the Gaia era". Astronomy & Astrophysics. 633: A34. arXiv:1910.12732. Bibcode:2020A&A...633A..34C. doi:10.1051/0004-6361/201936360. eISSN 1432-0746. ISSN 0004-6361.
  8. ^ a b Kervella, Pierre; Arenou, Frédéric; Thévenin, Frédéric (2022). "Stellar and substellar companions from Gaia EDR3". Astronomy & Astrophysics. 657: A7. arXiv:2109.10912. Bibcode:2022A&A...657A...7K. doi:10.1051/0004-6361/202142146. eISSN 1432-0746. ISSN 0004-6361.
  9. ^ a b Anders, F.; et al. (August 2019). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18". Astronomy & Astrophysics. 628: A94. arXiv:1904.11302. Bibcode:2019A&A...628A..94A. doi:10.1051/0004-6361/201935765. eISSN 1432-0746. ISSN 0004-6361.
  10. ^ 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.
  11. ^ 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". Astronomy & Astrophysics. 561: A126. arXiv:1312.3474. Bibcode:2014A&A...561A.126D. doi:10.1051/0004-6361/201220762. eISSN 1432-0746. ISSN 0004-6361.
  12. ^ 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.
  13. ^ "HD 106248". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved October 18, 2022.
  14. ^ Eggen, O. J. (July 1993). "Evolved GK stars near the sun. I - The old disk population". The Astronomical Journal. 106: 80. Bibcode:1993AJ....106...80E. doi:10.1086/116622.
  15. ^ Janes, K. A.; McClure, Robert D. (May 1971). "Strong-Cyanogen Stars: Photometry and Kinematics". The Astrophysical Journal. 165: 561. Bibcode:1971ApJ...165..561J. doi:10.1086/150921. eISSN 1538-4357. ISSN 0004-637X.