Astronomy:HR 7135
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Aquila |
| Right ascension | 18h 55m 27.46151s[1] |
| Declination | +06° 36′ 55.1499″[1] |
| Apparent magnitude (V) | 5.57[2] |
| Characteristics | |
| Spectral type | G9 III[3] |
| U−B color index | +0.87[2] |
| B−V color index | +1.041±0.002[4] |
| Astrometry | |
| Radial velocity (Rv) | 23.31±0.09[5] km/s |
| Proper motion (μ) | RA: +7.972[1] mas/yr Dec.: –92.211[1] mas/yr |
| Parallax (π) | 11.5405 ± 0.1636[1] mas |
| Distance | 283 ± 4 ly (87 ± 1 pc) |
| Absolute magnitude (MV) | 0.87[4] |
| Orbit[5][6] | |
| Primary | HR 7135 A |
| Companion | HR 7135 B |
| Period (P) | 2,994±29 d |
| Semi-major axis (a) | 26.6±3.4 mas |
| Eccentricity (e) | 0.243±0.026 |
| Inclination (i) | 31.9±3.6° |
| Longitude of the node (Ω) | 12.6±7.7° |
| Periastron epoch (T) | 2444276.5±52 JD |
| Argument of periastron (ω) (secondary) | 35±7° |
| Semi-amplitude (K1) (primary) | 4.65±0.13 km/s |
| Details | |
| HR 7135 A | |
| Mass | 1.54[7] M☉ |
| Radius | 10.69+0.17 −0.93[1] R☉ |
| Luminosity | 52.8±0.9[1] L☉ |
| Surface gravity (log g) | 2.7[8] cgs |
| Temperature | 4,666±51[7] K |
| Metallicity [Fe/H] | –0.26[8] dex |
| Rotational velocity (v sin i) | 0.0[8] km/s |
| Age | 3.21[7] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
HR 7135 is a binary star system. Despite its Flamsteed designation of 62 Serpentis, the star can be found in the equatorial constellation of Aquila,[10] in front of a dark rift in the Milky Way near the constellation border.[5] It is visible to the naked eye as a dim, yellow-hued point of light with an apparent visual magnitude of 5.57.[2] The system is located 283 light years distant from the Sun, based on parallax,[1] and is drifting further away with a radial velocity of 23 km/s.[5]
Discovery of the binary nature of this system is credited to Canadian astronomer H. H. Plaskett in 1922. It is a single-lined spectroscopic binary with an orbital period of 8.2 years and an eccentricity of 0.24.[5][6] The visible component is an aging giant star with a stellar classification of G9 III,[3] having exhausted the supply of hydrogen at its core and expanded to 10.7[1] times the Sun's radius. It is a red clump giant, indicating it is on the horizontal branch and is generating energy via core helium fusion.[11] The star is 3.2[7] billion years old with 1.54[7] times the mass of the Sun. It is radiating 53[1] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,666 K.[7] The star has a very low rate of spin, with the projected rotational velocity being too small to measure.[8]
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 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. Bibcode: 2018A&A...616A...1G. Gaia DR2 record for this source at VizieR.
- ↑ 2.0 2.1 2.2 Johnson, H. L. et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory 4 (99): 99, Bibcode: 1966CoLPL...4...99J.
- ↑ 3.0 3.1 McWilliam, Andrew (December 1990), "High-resolution spectroscopic survey of 671 GK giants. I - Stellar atmosphere parameters and abundances", Astrophysical Journal Supplement Series 74: 1075–1128, doi:10.1086/191527, Bibcode: 1990ApJS...74.1075M
- ↑ 4.0 4.1 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode: 2012AstL...38..331A.
- ↑ 5.0 5.1 5.2 5.3 5.4 Griffin, R. F. (1981), "Spectroscopic binary orbits from photoelectric radial velocities. Paper 41: HR 7135", The Observatory 101: 208–211, Bibcode: 1981Obs...101..208G.
- ↑ 6.0 6.1 Jancart, S. et al. (2005), "Astrometric orbits of SB9 stars", Astronomy and Astrophysics 442 (1): 365–380, doi:10.1051/0004-6361:20053003, Bibcode: 2005A&A...442..365J.
- ↑ 7.0 7.1 7.2 7.3 7.4 7.5 Luck, R. Earle (2015), "Abundances in the Local Region. I. G and K Giants", Astronomical Journal 150 (3): 88, doi:10.1088/0004-6256/150/3/88, Bibcode: 2015AJ....150...88L.
- ↑ 8.0 8.1 8.2 8.3 Massarotti, 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, doi:10.1088/0004-6256/135/1/209, Bibcode: 2008AJ....135..209M.
- ↑ "HD 175515". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+175515.
- ↑ Kaler, James B. (1996), The ever-changing sky: a guide to the celestial sphere, Cambridge University Press, pp. 119, ISBN 0-521-38053-7, https://books.google.com/books?id=KYLSMsduNqcC.
- ↑ Alves, David R. (August 2000), "K-Band Calibration of the Red Clump Luminosity", The Astrophysical Journal 539 (2): 732–741, doi:10.1086/309278, Bibcode: 2000ApJ...539..732A.
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