Astronomy:HD 44120

From HandWiki
Short description: Binary star system in the constellation Pictor
HD 44120
Observation data
Equinox J2000.0]] (ICRS)
Constellation Pictor
Right ascension  06h 16m 18.786s[1]
Declination −59° 12′ 48.61″[1]
Apparent magnitude (V) 6.44[2] + 14.03[3]
Characteristics
Spectral type F9.5V[4] + DB3.2[3]
B−V color index 0.593±0.015[2]
Astrometry
A
Radial velocity (Rv)−2.125±0.0003[5] km/s
Proper motion (μ) RA: −45.187[1] mas/yr
Dec.: −316.389[1] mas/yr
Parallax (π)27.7563 ± 0.0172[1] mas
Distance117.51 ± 0.07 ly
(36.03 ± 0.02 pc)
Absolute magnitude (MV)3.57[2]
Details
A
Mass1.214±0.040[6] M
Radius1.58+0.02
−0.05
[7] R
Luminosity2.952±0.005[7] L
Surface gravity (log g)4.10±0.03[8] cgs
Temperature6,005±70[8] K
Metallicity [Fe/H]0.09±0.06[8] dex
Rotational velocity (v sin i)3.39[9] km/s
Age4.105±0.755[6] Gyr
C
Mass0.67±0.10[10] M
Radius0.0130±0.0003[10] R
Surface gravity (log g)8.04±0.06[10] cgs
Temperature15,746±238[10] K
Other designations
GJ 9209, WDS J06163-5913[11]
A: {{{names1}}}
C: L 182-61, WD 0615-591[3]
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.[2] 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.[5] It has an absolute magnitude of 3.57.[2]

The primary member, designated component A of this system, is an F-type main-sequence star with a stellar classification of F9.5V.[4] It is a Sun-like star and has been considered a "hot" solar analog with a shallower convection zone than the Sun.[12] The estimated age of this star is about four billion years,[6] and it is spinning with a projected rotational velocity of 3.4 km/s.[9] It is chromospherically inactive.[13] The star has 1.2[6] times the mass of the Sun and 1.6[7] times the Sun's radius. It is radiating nearly three[7] times the luminosity of the Sun from its photosphere at an effective temperature of 6,005 K.[8]

The faint secondary companion, component C, is a magnitude 14.03 white dwarf star with a class of DB3.2,[3] 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.[10] 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.[14] 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 astronomical unit|AU. Their estimated orbit has a semimajor axis of 1,702.6 AU and an orbital period of 51,100 years.[3]

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.[15] The parallax for this star indicates a distance of approximately 215 ly (66 pc) from the Sun.[16]

References

  1. 1.0 1.1 1.2 1.3 Brown, A. G. A. (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics 649: A1. doi:10.1051/0004-6361/202039657. Bibcode2021A&A...649A...1G.  Gaia EDR3 record for this source at VizieR.
  2. 2.0 2.1 2.2 2.3 2.4 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode2012AstL...38..331A 
  3. 3.0 3.1 3.2 3.3 3.4 Holberg, J. B. et al. (2013), "Where are all the Sirius-like binary systems?", Monthly Notices of the Royal Astronomical Society 435 (3): 2077, doi:10.1093/mnras/stt1433, Bibcode2013MNRAS.435.2077H 
  4. 4.0 4.1 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, doi:10.1086/504637, Bibcode2006AJ....132..161G 
  5. 5.0 5.1 Soubiran, C. et al. (2018), "Gaia Data Release 2. The catalogue of radial velocity standard stars", Astronomy and Astrophysics 616: A7, doi:10.1051/0004-6361/201832795, Bibcode2018A&A...616A...7S 
  6. 6.0 6.1 6.2 6.3 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, doi:10.1051/0004-6361/201834783, A78, Bibcode2019A&A...624A..78D 
  7. 7.0 7.1 7.2 7.3 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  8. 8.0 8.1 8.2 8.3 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, doi:10.1051/0004-6361/201732209, A55, Bibcode2018A&A...614A..55A 
  9. 9.0 9.1 Delgado Mena, E. et al. (April 2015), "Li abundances in F stars: planets, rotation, and Galactic evolution", Astronomy & Astrophysics 576: 24, doi:10.1051/0004-6361/201425433, A69, Bibcode2015A&A...576A..69D 
  10. 10.0 10.1 10.2 10.3 10.4 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, doi:10.3847/1538-4357/aa8bb6, Bibcode2017ApJ...848...11B 
  11. "HD 44120". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+44120. 
  12. 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 282: pp. 480–481, doi:10.1017/S1743921311028183, Bibcode2012IAUS..282..480G 
  13. Mason, Brian D. et al. (December 1998), "A Multiplicity Survey of Chromospherically Active and Inactive Stars", The Astronomical Journal 116 (6): 2975–2983, doi:10.1086/300654, Bibcode1998AJ....116.2975M 
  14. Zhao, J. K. et al. (February 2012), "The Initial-Final Mass Relation among White Dwarfs in Wide Binaries", The Astrophysical Journal 746 (2): 11, doi:10.1088/0004-637X/746/2/144, 144, Bibcode2012ApJ...746..144Z 
  15. Mason, B. D. et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal 122 (6): 3466–3471, doi:10.1086/323920, Bibcode2001AJ....122.3466M 
  16. Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.

Coordinates: Sky map 06h 16m 19s, −59° 12′ 49″