Astronomy:HD 165259

From HandWiki
Short description: Triple star system in the constellation Apus
HD 165259
Observation data
{{#ifeq:J2000.0 (ICRS)|J2000.0 (ICRS)|Epoch J2000.0      Equinox J2000.0 (ICRS)| [[History:Epoch|Epoch J2000.0 (ICRS)]]      [[Astronomy:Equinox (celestial coordinates)|Equinox J2000.0 (ICRS)}}
Constellation Apus
A
Right ascension  18h 12m 34.08358s[1]
Declination −73° 40′ 20.7691″[1]
Apparent magnitude (V) 5.91[2]
B
Right ascension  18h 12m 33.47381s[3]
Declination −73° 40′ 20.9419″[3]
Apparent magnitude (V) 9.03[2]
Characteristics
A
Spectral type F5V[4]
U−B color index +0.05[5]
B−V color index +0.46[5]
B
Spectral type G1 V[6]
U−B color index +0.74[6]
B−V color index +1.06[6]
Astrometry
Radial velocity (Rv)13.1±1[7] km/s
Absolute magnitude (MV)+2.74[8]
A
Proper motion (μ) RA: −91.400[1] mas/yr
Dec.: −254.341[1] mas/yr
Parallax (π)23.6778 ± 0.0399[1] mas
Distance137.7 ± 0.2 ly
(42.23 ± 0.07 pc)
B
Proper motion (μ) RA: −62.130[3] mas/yr
Dec.: −241.999[3] mas/yr
Parallax (π)23.7101 ± 0.0338[3] mas
Distance137.6 ± 0.2 ly
(42.18 ± 0.06 pc)
Orbit[9]
PrimaryA
CompanionB
Period (P)542 yr
Semi-major axis (a)98 astronomical unit|AU
Orbit[9]
PrimaryAa
CompanionAb
Period (P)31.536 yr
Semi-major axis (a)13.3 astronomical unit|AU
Details
Aa
Mass1.22[10] M
Radius2.04[1] R
Luminosity6.2[1] L
Surface gravity (log g)3.92[11] cgs
Temperature6,411±218[11] K
Metallicity [Fe/H]+0.26[12] dex
Rotational velocity (v sin i)<5[13] km/s
Age1.8+0.1−0.2[13] Gyr
Ab
Mass0.76[9] M
B
Mass0.85[9] M
Surface gravity (log g)4.3[14] cgs
Temperature5,328[14] K
Metallicity [Fe/H]−0.22[14] dex
Other designations
CD−73°1348, CPD−73°1888, GC 24731, HD 165259, HIP 89234, HR 6751, SAO 257571, WDS J18126-7340AB[15]
Database references
SIMBADdata

HD 165259, also known as HR 6751 is a triple star system located in the southern circumpolar constellation of Apus. It has an apparent magnitude of 5.86,[8] making it faintly visible to the naked eye Parallax measurements place the system at a distance of 138 light years,[1][3] and it is currently receding with a heliocentric radial velocity of 13.1 km/s.[7]

HD 165259 consists of two main sequence stars, with stellar classifications of F5 V[4] and G1 V,[6] separated by two arc-seconds as of 2020.[16] Speckle interferometry in 2008 revealed the primary to be a close binary itself, with the two components separated by 0.3.[17] By 2020, the separation had decreased to 0.2.[16] The outer pair take 542 years to complete a revolution while the inner pair complete their orbit within 32 years.[9]

At present the primary has 122% the mass of the Sun[10] and a slightly enlarged radius of 2.0 R as it is nearing the end of its main sequence life.[1] It radiates at 6.2 times the luminosity of the Sun[1] from its photosphere at an effective temperature of 6,411 K,[11] giving a yellow-white hue. HD 165259A has an iron abundance 82% above solar levels,[12] making it metal enriched. It is estimated to be nearly 2 billion years old and has a projected rotational velocity of less than km/s.[13] HD 165259B has 85% the mass of the Sun[9] and an effective temperature of 5,328 K,[14] giving an orange glow. The faint star orbiting the primary has a mass 76% that of the Sun.[9]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940  Gaia DR3 record for this source at VizieR.
  2. 2.0 2.1 Fabricius, C.; Høg, E.; Makarov, V. V.; Mason, B. D.; Wycoff, G. L.; Urban, S. E. (March 2002). "The Tycho double star catalogue". Astronomy & Astrophysics 384 (1): 180–189. doi:10.1051/0004-6361:20011822. ISSN 0004-6361. Bibcode2002A&A...384..180F. 
  3. 3.0 3.1 3.2 3.3 3.4 3.5 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940  Gaia DR3 record for this source at VizieR.
  4. 4.0 4.1 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°. Bibcode1975mcts.book.....H. 
  5. 5.0 5.1 Nicolet, B. (1978). "Photoelectric photometric Catalogue of homogeneous measurements in the UBV System". Astronomy and Astrophysics Supplement Series 34: 1–49. Bibcode1978A&AS...34....1N. 
  6. 6.0 6.1 6.2 6.3 Corbally, C. J. (August 1984). "Close visual binaries. I - MK classifications". The Astrophysical Journal Supplement Series 55: 657. doi:10.1086/190973. ISSN 0067-0049. Bibcode1984ApJS...55..657C. 
  7. 7.0 7.1 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. doi:10.1134/S1063773706110065. ISSN 1063-7737. Bibcode2006AstL...32..759G. 
  8. 8.0 8.1 Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331–346. doi:10.1134/S1063773712050015. ISSN 1063-7737. Bibcode2012AstL...38..331A. 
  9. 9.0 9.1 9.2 9.3 9.4 9.5 9.6 Tokovinin, Andrei (14 March 2014). "From Binaries to Multiples. II. Hierarchical Multiplicity of F and G Dwarfs". The Astronomical Journal 147 (4): 87. doi:10.1088/0004-6256/147/4/87. ISSN 0004-6256. Bibcode2014AJ....147...87T. 
  10. 10.0 10.1 Anders, F.; Khalatyan, A.; Chiappini, C.; Queiroz, A. B.; Santiago, B. X.; Jordi, C.; Girardi, L.; Brown, A. G. A. et al. (August 2019). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18". Astronomy & Astrophysics 628: A94. doi:10.1051/0004-6361/201935765. ISSN 0004-6361. Bibcode2019A&A...628A..94A. 
  11. 11.0 11.1 11.2 David, Trevor J.; Hillenbrand, Lynne A. (12 May 2015). "The Ages of Early-type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets". The Astrophysical Journal 804 (2): 146. doi:10.1088/0004-637X/804/2/146. Bibcode2015ApJ...804..146D. 
  12. 12.0 12.1 Casagrande, L.; Schönrich, R.; Asplund, M.; Cassisi, S.; Ramírez, I.; Meléndez, J.; Bensby, T.; Feltzing, S. (26 May 2011). "New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s): Improved astrophysical parameters for the Geneva-Copenhagen Survey⋆". Astronomy & Astrophysics 530: A138. doi:10.1051/0004-6361/201016276. ISSN 0004-6361. Bibcode2011A&A...530A.138C. 
  13. 13.0 13.1 13.2 Nordström, B.; Mayor, M.; Andersen, J.; Holmberg, J.; Pont, F.; Jørgensen, B. R.; Olsen, E. H.; Udry, S. et al. (16 April 2004). "The Geneva-Copenhagen survey of the Solar neighbourhood". Astronomy & Astrophysics 418 (3): 989–1019. doi:10.1051/0004-6361:20035959. ISSN 0004-6361. Bibcode2004A&A...418..989N. 
  14. 14.0 14.1 14.2 14.3 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. doi:10.1051/0004-6361/202142369. ISSN 0004-6361. Bibcode2022A&A...658A..91A. 
  15. "HR 6635". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HR+6635. 
  16. 16.0 16.1 Mason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (December 2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog". The Astronomical Journal 122 (6): 3466–3471. doi:10.1086/323920. ISSN 0004-6256. Bibcode2001AJ....122.3466M. 
  17. Tokovinin, Andrei; Mason, Brian D.; Hartkopf, William I. (2010). "Speckle Interferometry at the Blanco and SOAR Telescopes in 2008 and 2009". The Astronomical Journal 139 (2): 743–756. doi:10.1088/0004-6256/139/2/743. Bibcode2010AJ....139..743T. 
Cite error: <ref> tag with name "Gould1879" defined in <references> is not used in prior text.

External links