HD 175740
| Observation data EpochJ2000.0EquinoxJ2000.0 | |
|---|---|
| Constellation | Lyra |
| Right ascension | 18h54m52.17758s[1] |
| Declination | +41° 36′ 09.7934″[1] |
| Apparent magnitude(V) | 5.46[2] |
| Characteristics | |
| Spectral type | K0III[3] |
| B−Vcolor index | 1.034±0.004[2] |
| Astrometry | |
| Radial velocity(Rv) | −9.52±0.13[4]km/s |
| Proper motion(μ) | RA:−2.059[1]mas/yr Dec.:−2.234[1]mas/yr |
| Parallax(π) | 12.2448 ± 0.0874mas[1] |
| Distance | 266 ± 2ly (81.7 ± 0.6pc) |
| Absolute magnitude(MV) | 0.89[2] |
| Details | |
| Mass | 1.39[5]or 2.795[4]M☉ |
| Radius | 10.17+0.35 −0.73[1]R☉ |
| Luminosity | 49.90±0.45[1]L☉ |
| Surface gravity(logg) | 2.8[6]cgs |
| Temperature | 4,811+181 −81[1]K |
| Metallicity[Fe/H] | −0.01±0.06[2]dex |
| Rotational velocity(vsini) | 4.0[6]km/s |
| Age | 4.78[5]Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
HD 175740is a single[8]starin the northernconstellationofLyra.[2]This object has an orange hue and is dimly visible to the naked eye with anapparent visual magnitudeof 5.46.[2]It is located at a distance of approximately 266light yearsfrom theSunbased onparallax,[1]and has anabsolute magnitudeof 0.89.[2]The star is drifting closer with aradial velocityof −9.5 km/s, and is predicted to come as close as 31.7 light-years in around 8 million years.[4]
This is an aginggiant starwith astellar classificationof K0III,[3]havingevolvingoff themain sequenceafter the supply of hydrogen at itscorewas exhausted. It is an estimated 4.78[5]billion years old with 1.39[5]times themass of the Sun,although Bailer-Jones et al. (2018) give a higher estimate of 2.8[4]times the Sun's mass. The elemental composition of this star has made it the first giant to be a candidate solar sibling, suggesting it may have been born in the samestar clusteras the Sun.[9]It has expanded to ten[1]times thegirth of the Sunand is radiating 50[1]times theSun's luminosityfrom itsphotosphereat aneffective temperatureof 4,811 K.[1]
HD 175740 has a magnitude 12.6 visual companion, located at anangular separationof8.4″along aposition angle(PA) of 300°, as of 2013. A magnitude 11.5 companion lies at a separation of24.1″along a PA of 39°, as of 2014. Both were discovered by American astronomerG. W. Houghin 1887.[10]
References
[edit]- ^abcdefghijklBrown, A. G. A.;et al. (Gaia collaboration) (August 2018)."GaiaData Release 2: Summary of the contents and survey properties ".Astronomy & Astrophysics.616.A1.arXiv:1804.09365.Bibcode:2018A&A...616A...1G.doi:10.1051/0004-6361/201833051.Gaia DR2 record for this sourceatVizieR.
- ^abcdefgAnderson, 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,S2CID119257644.
- ^abAbt, H. A. (September 1985), "Visual multiples. VIII - 1000 MK types",Astrophysical Journal Supplement Series,59:95–112,Bibcode:1985ApJS...59...95A,doi:10.1086/191064
- ^abcdBailer-Jones, C.A.L.; et al. (2018), "New stellar encounters discovered in the second Gaia data release",Astronomy & Astrophysics,616:A37,arXiv:1805.07581,Bibcode:2018A&A...616A..37B,doi:10.1051/0004-6361/201833456,S2CID56269929.
- ^abcdLuck, R. Earle (2015), "Abundances in the Local Region. I. G and K Giants",Astronomical Journal,150(3), 88,arXiv:1507.01466,Bibcode:2015AJ....150...88L,doi:10.1088/0004-6256/150/3/88,S2CID118505114.
- ^abMassarotti, Alessandro; et al. (January 2008), "Rotational and Radial Velocities for a Sample of 761 HIPPARCOS Giants and the Role of Binarity",The Astronomical Journal,135(1): 209–231,Bibcode:2008AJ....135..209M,doi:10.1088/0004-6256/135/1/209.
- ^"HD 175740".SIMBAD.Centre de données astronomiques de Strasbourg.Retrieved2020-02-09.
- ^Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems",Monthly Notices of the Royal Astronomical Society,389(2): 869–879,arXiv:0806.2878,Bibcode:2008MNRAS.389..869E,doi:10.1111/j.1365-2966.2008.13596.x,S2CID14878976.
- ^Ramírez, I.; et al. (June 2014), "Elemental Abundances of Solar Sibling Candidates",The Astrophysical Journal,787(2): 17,arXiv:1405.1723,Bibcode:2014ApJ...787..154R,doi:10.1088/0004-637X/787/2/154,S2CID118441281,154.
- ^Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog",The Astronomical Journal,122(6): 3466,Bibcode:2001AJ....122.3466M,doi:10.1086/323920.