| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Hercules |
| Right ascension | 17h 57m 14.33667s [1] |
| Declination | +23° 59′ 44.5562″ [1] |
| Apparent magnitude (V) | 6.4543±0.0005 [1] (6.30 + 7.90) [2] |
| Characteristics | |
| Spectral type | G2 V + K2 V [3] |
| B−V color index | 0.642±0.006 [1] |
| Astrometry | |
| Radial velocity (Rv) | −32.83±0.07 [4] km/s |
| Proper motion (μ) |
RA: −17.79±0.33
[1]
mas/
yr Dec.: +73.56±0.47 [1] mas/ yr |
| Parallax (π) | 35.40 ± 0.62 mas [1] |
| Distance | 92 ± 2
ly (28.2 ± 0.5 pc) |
| Absolute magnitude (MV) | 4.05 [5] |
| Orbit [6] | |
| Period (P) | 881.628±0.064 d |
| Semi-major axis (a) | 80.64 mas |
| Eccentricity (e) | 0.4165±0.0010 |
| Inclination (i) | 72.83±0.47° |
| Longitude of the node (Ω) | 175.32±0.44° |
| Periastron epoch (T) | 55650.39 ± 0.38 (BJD−2400000) |
|
Argument of periastron (ω) (secondary) | 135.46±0.16° |
| Details | |
| HD 163840 A | |
| Mass | 1.132±0.014 [6] M☉ |
| Luminosity | 2.031 [3] L☉ |
| Temperature | 5,860 [3] K |
| Metallicity [Fe/H] | 0.06 [5] dex |
| Age | 7.4 [5] Gyr |
| HD 163840 B | |
| Mass | 0.7421±0.0073 [6] M☉ |
| Luminosity | 0.648 [3] L☉ |
| Temperature | 4,780 [3] K |
| Other designations | |
| Database references | |
| SIMBAD | data |
HD 163840 is a binary star [6] system in the northern constellation of Hercules. It has a combined apparent visual magnitude of 6.45, [1] which falls just below the brightness level that is visible to the naked eye for people with normal eyesight. An annual parallax shift of 35.40 [1] mas provides a distance estimate of about 92 light years. The system is moving closer to the Sun with a radial velocity of −33 km/s. [4] In about 769,000 years, it will make perihelion at a separation of around 27.2 ly (8.33 pc). [8]
R. K. Young of the Dominion Astrophysical Observatory was the first to recognize the variable radial velocity of this system. [9] In 1974, Harold A. McAlister and Philip A. Ianna identified it as a nearby G-type dwarf based on its spectroscopic properties. [10] McAlister et al. (1974) found it to be a spectroscopic binary [10] and the components were first resolved in 1976. A series of observations since that time allowed the system's orbital elements to be published by McAlister et al. (1995), along with estimates of the stellar masses of the two components. [11] These parameters have been further refined using improved instruments up through 2016. [6]
The pair of stars orbit each other with a period of 881.6 days (2.414 a) and an eccentricity of 0.417. The plane of their orbit is inclined by an angle of 73° to the line of sight from the Earth, with a semimajor axis having an angular value of 80.64 mas. [6] The close, eccentric orbit of the pair does not permit a stable planetary orbit in the habitable zone of either component. [3]
The primary, component A, is a magnitude 6.30 [2] G-type main-sequence star with a stellar classification of G2 V. [3] It has 1.13 [6] times the mass of the Sun and is radiating double the Sun's luminosity from its photosphere at an effective temperature of 5,860 K. [3] Component B, the magnitude 7.90 [2] secondary, is a smaller K-type main-sequence star with a class of K2 V. [3] It has 0.74 [6] times the Sun's mass and shines with 0.65 [3] times the Sun's luminosity at an effective temperature of 4,780 K. [3] The system as a whole may be around 7.4 [5] billion years old with a slightly higher metallicity than the Sun. The system displays solar-like variability. [12]
- ^ a b c d e f g h i van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv: 0708.1752, Bibcode: 2007A&A...474..653V, doi: 10.1051/0004-6361:20078357, S2CID 18759600.
- ^ a b c 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
- ^ a b c d e f g h i j k Eggl, S.; et al. (2012), "Circumstellar habitable zones of binary-star systems in the solar neighbourhood", Monthly Notices of the Royal Astronomical Society, 428 (4): 3104, arXiv: 1210.5411, Bibcode: 2013MNRAS.428.3104E, doi: 10.1093/mnras/sts257.
- ^ a b Pourbaix, D.; et al. (2004), "SB9: The Ninth Catalogue of Spectroscopic Binary Orbits", Astronomy & Astrophysics, 424: 727–732, arXiv: astro-ph/0406573, Bibcode: 2004A&A...424..727P, doi: 10.1051/0004-6361:20041213, S2CID 119387088.
- ^ a b c d Holmberg, J.; et al. (July 2009), "The Geneva-Copenhagen survey of the solar neighbourhood. III. Improved distances, ages, and kinematics", Astronomy and Astrophysics, 501 (3): 941–947, arXiv: 0811.3982, Bibcode: 2009A&A...501..941H, doi: 10.1051/0004-6361/200811191, S2CID 118577511.
- ^ a b c d e f g h Kiefer, F.; et al. (May 2016), "Masses of the components of SB2 binaries observed with Gaia - III. Accurate SB2 orbits for 10 binaries and masses of HIP 87895", Monthly Notices of the Royal Astronomical Society, 458 (3): 3272−3281, arXiv: 1603.02861, Bibcode: 2016MNRAS.458.3272K, doi: 10.1093/mnras/stw545.
- ^ "HD 163840". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-01-12.
- ^ Bailer-Jones, C. A. L. (March 2015), "Close encounters of the stellar kind", Astronomy & Astrophysics, 575: 13, arXiv: 1412.3648, Bibcode: 2015A&A...575A..35B, doi: 10.1051/0004-6361/201425221, S2CID 59039482, A35.
- ^ Culver, R.; et al. (September 1980), "HR 6697: A Nearby G-Star Binary System", Bulletin of the American Astronomical Society, 12: 850, Bibcode: 1980BAAS...12..850C.
- ^ a b McAlister, Harold A.; Ianna, Philip A. (October 1974), "Possible Nearby F and G Dwarfs", Publications of the Astronomical Society of the Pacific, 86 (513): 769, Bibcode: 1974PASP...86..769M, doi: 10.1086/129672.
- ^ McAlister, H. A.; et al. (July 1995), "Binary Star Orbits from Speckle Interferometry. VI. The Nearby Solar-Type Speckle-Spectroscopic Binary HR 6697", Astronomical Journal, 110: 366, Bibcode: 1995AJ....110..366M, doi: 10.1086/117527.
- ^ Hall, Jeffrey C.; et al. (March 2007), "The Activity and Variability of the Sun and Sun-like Stars. I. Synoptic Ca II H and K Observations", The Astronomical Journal, 133 (3): 862–881, Bibcode: 2007AJ....133..862H, doi: 10.1086/510356.
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Hercules |
| Right ascension | 17h 57m 14.33667s [1] |
| Declination | +23° 59′ 44.5562″ [1] |
| Apparent magnitude (V) | 6.4543±0.0005 [1] (6.30 + 7.90) [2] |
| Characteristics | |
| Spectral type | G2 V + K2 V [3] |
| B−V color index | 0.642±0.006 [1] |
| Astrometry | |
| Radial velocity (Rv) | −32.83±0.07 [4] km/s |
| Proper motion (μ) |
RA: −17.79±0.33
[1]
mas/
yr Dec.: +73.56±0.47 [1] mas/ yr |
| Parallax (π) | 35.40 ± 0.62 mas [1] |
| Distance | 92 ± 2
ly (28.2 ± 0.5 pc) |
| Absolute magnitude (MV) | 4.05 [5] |
| Orbit [6] | |
| Period (P) | 881.628±0.064 d |
| Semi-major axis (a) | 80.64 mas |
| Eccentricity (e) | 0.4165±0.0010 |
| Inclination (i) | 72.83±0.47° |
| Longitude of the node (Ω) | 175.32±0.44° |
| Periastron epoch (T) | 55650.39 ± 0.38 (BJD−2400000) |
|
Argument of periastron (ω) (secondary) | 135.46±0.16° |
| Details | |
| HD 163840 A | |
| Mass | 1.132±0.014 [6] M☉ |
| Luminosity | 2.031 [3] L☉ |
| Temperature | 5,860 [3] K |
| Metallicity [Fe/H] | 0.06 [5] dex |
| Age | 7.4 [5] Gyr |
| HD 163840 B | |
| Mass | 0.7421±0.0073 [6] M☉ |
| Luminosity | 0.648 [3] L☉ |
| Temperature | 4,780 [3] K |
| Other designations | |
| Database references | |
| SIMBAD | data |
HD 163840 is a binary star [6] system in the northern constellation of Hercules. It has a combined apparent visual magnitude of 6.45, [1] which falls just below the brightness level that is visible to the naked eye for people with normal eyesight. An annual parallax shift of 35.40 [1] mas provides a distance estimate of about 92 light years. The system is moving closer to the Sun with a radial velocity of −33 km/s. [4] In about 769,000 years, it will make perihelion at a separation of around 27.2 ly (8.33 pc). [8]
R. K. Young of the Dominion Astrophysical Observatory was the first to recognize the variable radial velocity of this system. [9] In 1974, Harold A. McAlister and Philip A. Ianna identified it as a nearby G-type dwarf based on its spectroscopic properties. [10] McAlister et al. (1974) found it to be a spectroscopic binary [10] and the components were first resolved in 1976. A series of observations since that time allowed the system's orbital elements to be published by McAlister et al. (1995), along with estimates of the stellar masses of the two components. [11] These parameters have been further refined using improved instruments up through 2016. [6]
The pair of stars orbit each other with a period of 881.6 days (2.414 a) and an eccentricity of 0.417. The plane of their orbit is inclined by an angle of 73° to the line of sight from the Earth, with a semimajor axis having an angular value of 80.64 mas. [6] The close, eccentric orbit of the pair does not permit a stable planetary orbit in the habitable zone of either component. [3]
The primary, component A, is a magnitude 6.30 [2] G-type main-sequence star with a stellar classification of G2 V. [3] It has 1.13 [6] times the mass of the Sun and is radiating double the Sun's luminosity from its photosphere at an effective temperature of 5,860 K. [3] Component B, the magnitude 7.90 [2] secondary, is a smaller K-type main-sequence star with a class of K2 V. [3] It has 0.74 [6] times the Sun's mass and shines with 0.65 [3] times the Sun's luminosity at an effective temperature of 4,780 K. [3] The system as a whole may be around 7.4 [5] billion years old with a slightly higher metallicity than the Sun. The system displays solar-like variability. [12]
- ^ a b c d e f g h i van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv: 0708.1752, Bibcode: 2007A&A...474..653V, doi: 10.1051/0004-6361:20078357, S2CID 18759600.
- ^ a b c 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
- ^ a b c d e f g h i j k Eggl, S.; et al. (2012), "Circumstellar habitable zones of binary-star systems in the solar neighbourhood", Monthly Notices of the Royal Astronomical Society, 428 (4): 3104, arXiv: 1210.5411, Bibcode: 2013MNRAS.428.3104E, doi: 10.1093/mnras/sts257.
- ^ a b Pourbaix, D.; et al. (2004), "SB9: The Ninth Catalogue of Spectroscopic Binary Orbits", Astronomy & Astrophysics, 424: 727–732, arXiv: astro-ph/0406573, Bibcode: 2004A&A...424..727P, doi: 10.1051/0004-6361:20041213, S2CID 119387088.
- ^ a b c d Holmberg, J.; et al. (July 2009), "The Geneva-Copenhagen survey of the solar neighbourhood. III. Improved distances, ages, and kinematics", Astronomy and Astrophysics, 501 (3): 941–947, arXiv: 0811.3982, Bibcode: 2009A&A...501..941H, doi: 10.1051/0004-6361/200811191, S2CID 118577511.
- ^ a b c d e f g h Kiefer, F.; et al. (May 2016), "Masses of the components of SB2 binaries observed with Gaia - III. Accurate SB2 orbits for 10 binaries and masses of HIP 87895", Monthly Notices of the Royal Astronomical Society, 458 (3): 3272−3281, arXiv: 1603.02861, Bibcode: 2016MNRAS.458.3272K, doi: 10.1093/mnras/stw545.
- ^ "HD 163840". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-01-12.
- ^ Bailer-Jones, C. A. L. (March 2015), "Close encounters of the stellar kind", Astronomy & Astrophysics, 575: 13, arXiv: 1412.3648, Bibcode: 2015A&A...575A..35B, doi: 10.1051/0004-6361/201425221, S2CID 59039482, A35.
- ^ Culver, R.; et al. (September 1980), "HR 6697: A Nearby G-Star Binary System", Bulletin of the American Astronomical Society, 12: 850, Bibcode: 1980BAAS...12..850C.
- ^ a b McAlister, Harold A.; Ianna, Philip A. (October 1974), "Possible Nearby F and G Dwarfs", Publications of the Astronomical Society of the Pacific, 86 (513): 769, Bibcode: 1974PASP...86..769M, doi: 10.1086/129672.
- ^ McAlister, H. A.; et al. (July 1995), "Binary Star Orbits from Speckle Interferometry. VI. The Nearby Solar-Type Speckle-Spectroscopic Binary HR 6697", Astronomical Journal, 110: 366, Bibcode: 1995AJ....110..366M, doi: 10.1086/117527.
- ^ Hall, Jeffrey C.; et al. (March 2007), "The Activity and Variability of the Sun and Sun-like Stars. I. Synoptic Ca II H and K Observations", The Astronomical Journal, 133 (3): 862–881, Bibcode: 2007AJ....133..862H, doi: 10.1086/510356.