HD 44120

HD 44120
Observation data
Epoch J2000.0      Equinox ICRS
Constellation Pictor
A
Right ascension 06h 16m 18.786s
Declination −59° 12′ 48.61″
Apparent magnitude (V) 6.44
B
Right ascension 06h 16m 14.257s
Declination −59° 12′ 27.41″
Apparent magnitude (V) 14.03
Characteristics
A
Evolutionary stage subgiant
Spectral type F9.5V
B−V color index 0.593±0.015
B
Evolutionary stage white dwarf
Spectral type DB3.2
Astrometry
A
Radial velocity (Rv)−2.125±0.0003 km/s
Proper motion (μ) RA: −45.187 mas/yr
Dec.: −316.389 mas/yr
Parallax (π)27.7563±0.0172 mas
Distance117.51 ± 0.07 ly
(36.03 ± 0.02 pc)
Absolute magnitude (MV)3.57
B
Radial velocity (Rv)40 km/s
Proper motion (μ) RA: −48.359 mas/yr
Dec.: −312.181 mas/yr
Parallax (π)27.7297±0.0203 mas
Distance117.62 ± 0.09 ly
(36.06 ± 0.03 pc)
Details
A
Mass1.214±0.040 M☉
Radius1.56 R☉
Luminosity2.93 L☉
Surface gravity (log g)4.10±0.03 cgs
Temperature6,005±70 K
Metallicity [Fe/H]0.09±0.06 dex
Rotational velocity (v sin i)3.39 km/s
Age4.105±0.755 Gyr
C
Mass0.67±0.10 M☉
Radius0.0130±0.0003 R☉
Surface gravity (log g)8.04±0.06 cgs
Temperature15,746±238 K
Other designations
GJ 9209, WDS J06163-5913
A: CD−59°1275, HD 44120, HIP 29788, HR 2274, SAO 234418
C: L 182-61, WD 0615-591
Database references
SIMBADA
C

HD 44120 is a wide binary star system in the southern constellation of Pictor. Although visible to the naked eye, it is a challenge to view having an apparent visual magnitude of 6.44. The system is located at a distance of 118 light years from the Sun based on parallax, but it is drifting closer with a radial velocity of −2 km/s. It has an absolute magnitude of 3.57.

The primary member, designated component A of this system, is an F-type main-sequence star with a stellar classification of F9.5V. It is a Sun-like star and has been considered a "hot" solar analog with a shallower convection zone than the Sun. The estimated age of this star is about four billion years, and it is spinning with a projected rotational velocity of 3.4 km/s. It is chromospherically inactive. The star has 1.2 times the mass of the Sun and 1.6 times the Sun's radius. It is radiating nearly three times the luminosity of the Sun from its photosphere at an effective temperature of 6,005 K.

The faint secondary companion, component C, is a magnitude 14.03 white dwarf star with a class of DB3.2, indicating a helium-rich atmosphere. The object has an effective temperature of ~15,700 K with 67% of the Sun's mass but only 1.3% of the Sun's radius. It has taken 155±16 Myr for the white dwarf to have cooled to the current temperature. Prior to leaving the main sequence, this star is estimated to have had 1.45+0.20
−0.16 M☉ and thus was the system primary. It has an angular separation of 40.98″ along a position angle of 301.6° from the current primary. The projected separation of this co-moving pair is 1,533.9 AU. Their estimated orbit has a semimajor axis of 1,702.6 AU and an orbital period of 51,100 years.

A magnitude 7.61 visual companion, HD 44105, or component B, lies at an angular separation of 32.50″ along a position angle of 234° from component A, as of 2015. It was discovered as a double star by the Scottish astronomer James Dunlop and announced in 1829. The parallax for this star indicates a distance of approximately 214 ly (66 pc) from the Sun.

References

  1. 1 2 3 4 5 6 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. XHIP record for this object at VizieR.
  2. 1 2 3 4 5 6 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.
  3. 1 2 3 4 5 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.
  4. 1 2 3 4 5 Holberg, J. B.; et al. (2013), "Where are all the Sirius-like binary systems?", Monthly Notices of the Royal Astronomical Society, 435 (3): 2077, arXiv:1307.8047, Bibcode:2013MNRAS.435.2077H, doi:10.1093/mnras/stt1433
  5. 1 2 Gray, R. O.; et al. (July 2006), "Contributions to the Nearby Stars (NStars) Project: spectroscopy of stars earlier than M0 within 40 pc—The Southern Sample", The Astronomical Journal, 132 (1): 161–170, arXiv:astro-ph/0603770, Bibcode:2006AJ....132..161G, doi:10.1086/504637, S2CID 119476992
  6. 1 2 Zhao, J. K.; et al. (February 2012), "The Initial-Final Mass Relation among White Dwarfs in Wide Binaries", The Astrophysical Journal, 746 (2): 11, arXiv:1112.0281, Bibcode:2012ApJ...746..144Z, doi:10.1088/0004-637X/746/2/144, S2CID 54874378, 144
  7. 1 2 Soubiran, C.; et al. (2018), "Gaia Data Release 2. The catalogue of radial velocity standard stars", Astronomy and Astrophysics, 616: A7, arXiv:1804.09370, Bibcode:2018A&A...616A...7S, doi:10.1051/0004-6361/201832795, S2CID 52952408
  8. ↑ Wegner, G. (1974). "A spectroscopic survey of southern hemisphere white dwarfs - IV. Radial velocities and space motions". Monthly Notices of the Royal Astronomical Society. 166 (2): 271. Bibcode:1974MNRAS.166..271W. doi:10.1093/mnras/166.2.271.
  9. 1 2 3 4 Delgado Mena, E.; et al. (April 2019), "Abundance to age ratios in the HARPS-GTO sample with Gaia DR2. Chemical clocks for a range of [Fe/H]", Astronomy & Astrophysics, 624: 24, arXiv:1902.02127, Bibcode:2019A&A...624A..78D, doi:10.1051/0004-6361/201834783, S2CID 90259810, A78
  10. 1 2 3 4 Stassun, Keivan G.; et al. (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.
  11. 1 2 3 4 Aguilera-Gómez, Claudia; et al. (June 2018), "Lithium abundance patterns of late-F stars: an in-depth analysis of the lithium desert", Astronomy & Astrophysics, 614: 15, arXiv:1803.05922, Bibcode:2018A&A...614A..55A, doi:10.1051/0004-6361/201732209, S2CID 62799777, A55
  12. 1 2 Delgado Mena, E.; et al. (April 2015), "Li abundances in F stars: planets, rotation, and Galactic evolution", Astronomy & Astrophysics, 576: 24, arXiv:1412.4618, Bibcode:2015A&A...576A..69D, doi:10.1051/0004-6361/201425433, S2CID 56051637, A69
  13. 1 2 3 4 5 Bédard, A.; et al. (2017), "Measurements of Physical Parameters of White Dwarfs: A Test of the Mass-Radius Relation", The Astrophysical Journal, 848 (1): 11, arXiv:1709.02324, Bibcode:2017ApJ...848...11B, doi:10.3847/1538-4357/aa8bb6, S2CID 119359723
  14. ↑ "HD 44120". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-11-26.
  15. ↑ González Hernández, J. I.; et al. (April 2012), Richards, M. T.; Hubeny, I. (eds.), "Searching for the Signatures of Terrestrial Planets in Hot Analogs", From Interacting Binaries to Exoplanets: Essential Modeling Tools, Proceedings of the International Astronomical Union, IAU Symposium, vol. 282, pp. 480–481, Bibcode:2012IAUS..282..480G, doi:10.1017/S1743921311028183
  16. ↑ Mason, Brian D.; et al. (December 1998), "A Multiplicity Survey of Chromospherically Active and Inactive Stars", The Astronomical Journal, 116 (6): 2975–2983, Bibcode:1998AJ....116.2975M, doi:10.1086/300654
  17. ↑ Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal, 122 (6): 3466–3471, Bibcode:2001AJ....122.3466M, doi:10.1086/323920
  18. ↑ 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.