(Redirected from
G 208-44/208-45)
 A blue band light curve for a flare of V1581 Cygni. The left-most point shows a 1 sigma error bar. Adapted from Cristaldi and Rodonò (1976) [1] | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Cygnus |
| GJ 1245 AC | |
| Right ascension | 19h 53m 55.142s [2] |
| Declination | +44° 24′ 44.39″ [2] |
| Apparent magnitude (V) | 13.46 / 16.75 [3] |
| GJ 1245 B | |
| Right ascension | 19h 53m 55.141s [4] |
| Declination | +44° 24′ 54.15″ [4] |
| Apparent magnitude (V) | 14.01 [3] |
| Characteristics | |
| Spectral type | M6V / M8V [5] / M6V [6] |
| Variable type | UV Cet [7] |
| Astrometry | |
| Radial velocity (Rv) | 3.93±0.38 [4] km/s |
| Proper motion (μ) |
RA: 349.363(56)
mas/
yr
[4] Dec.: −480.322(54) mas/ yr [4] |
| Parallax (π) | 214.5745 ± 0.0476 mas [4] |
| Distance | 15.200 ± 0.003
ly (4.660 ± 0.001 pc) |
| Absolute magnitude (MV) | 15.12 / 18.41 [5] / 15.72 [3] |
| Orbit [8] | |
| Primary | GJ 1245 A |
| Companion | GJ 1245 C |
| Period (P) | 6147±17 d |
| Semi-major axis (a) | 0.8267±0.0008″ |
| Eccentricity (e) | 0.334±0.002 |
| Inclination (i) | 135.7±0.1° |
| Longitude of the node (Ω) | 261.2±0.2° |
| Periastron epoch (T) | 51506.8±2.1 |
|
Argument of periastron (ω) (secondary) | 36.1±0.2° |
| Details | |
| GJ 1245 A | |
| Mass | 0.120±0.001 [5] M☉ |
| Radius | 0.146±0.007 [5] R☉ |
| Luminosity | 0.0014 [5] L☉ |
| Temperature | 2,927 [5] K |
| Metallicity [Fe/H] | -0.07 [5] dex |
| Age | ~300[ citation needed] Myr |
| GJ 1245 C | |
| Mass | 0.081±0.001 [5] M☉ |
| Radius | 0.087±0.004 [5] R☉ |
| Luminosity | 0.0003 [5] L☉ |
| Temperature | 2,611 [5] K |
| Metallicity [Fe/H] | -0.08 [5] dex |
| Other designations | |
| GJ 1245 AC: G 208-44, LHS 3494, NLTT 48414, KIC 8451868, 2MASS J19535443+4424541 [9] | |
| GJ 1245 B: G 208-45, LHS 3495, NLTT 48415, KIC 8451881, 2MASS J19535508+4424550 [6] | |
| Database references | |
| SIMBAD | The system |
| A | |
| C | |
| B | |
  GJ 1245 Location of GJ 1245 in the constellation
Cygnus | |
GJ 1245 (Gliese 1245) is a double star with components G 208-44 and G 208-45, located 15.2 light-years (4.7 parsecs) away in the constellation Cygnus. G 208-44 is itself a closer double star made up of two red dwarfs, while G 208-45 is also a red dwarf. GJ 1245 is the 43rd closest stellar system to the Solar System. [10] GJ 1245 A and B are active flare stars, [11] and the pair are collectively designated V1581 Cygni. [12]
The largest of the three stars, GJ 1245 A (G 208-44 A) is only 12% the Sun's mass. [5] Of the other two stars, GJ 1245 C (G 208-44 B), is closest to star A at 2 AU away; [13] it is 8% of the Sun's mass. [5] The third star, GJ 1245 B (G 208-45), is 27 AU away from star A, [13] and is 10% of the Sun's mass; it would appear as bright as Venus does from Earth when viewed from star A.[ citation needed]
See also
References
- ^ Cristaldi, S.; Rodonò, M. (April 1976). "Discovery of Flare Activity in the Visual Binary G 208-44/45". Astronomy and Astrophysics. 48: 165. Bibcode: 1976A&A....48..165C. Retrieved 28 December 2021.
- ^ a b Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv: 2208.00211. Bibcode: 2023A&A...674A...1G. doi: 10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ a b c "The One Hundred Nearest Star Systems". RECONS. Retrieved 2016-08-21.
- ^ a b c d e Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv: 2208.00211. Bibcode: 2023A&A...674A...1G. doi: 10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ a b c d e f g h i j k l m n Dieterich, Serge B.; Simler, Andrew; Henry, Todd J.; Jao, Wei-Chun (April 2021). "The Solar Neighborhood. XLVII. Comparing M-dwarf Models with Hubble Space Telescope Dynamical Masses and Spectroscopy". The Astronomical Journal. 161 (4): 172. arXiv: 2012.00915. Bibcode: 2021AJ....161..172D. doi: 10.3847/1538-3881/abd2c2.
- ^ a b "G 208-45". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 11 June 2024.
- ^ Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1. Bibcode: 2009yCat....102025S.
- ^ Benedict, G. F.; Henry, T. J.; et al. (November 2016). "The Solar Neighborhood. XXXVII: The Mass-Luminosity Relation for Main-sequence M Dwarfs". The Astronomical Journal. 152 (5): 141. arXiv: 1608.04775. Bibcode: 2016AJ....152..141B. doi: 10.3847/0004-6256/152/5/141.
- ^ "G 208-44". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 11 June 2024.
- ^ Reylé, Céline; Jardine, Kevin; Fouqué, Pascal; Caballero, Jose A.; Smart, Richard L.; Sozzetti, Alessandro (30 April 2021). "The 10 parsec sample in the Gaia era". Astronomy & Astrophysics. 650: A201. arXiv: 2104.14972. Bibcode: 2021A&A...650A.201R. doi: 10.1051/0004-6361/202140985. S2CID 233476431. Data available at https://gruze.org/10pc/ Archived 12 March 2023 at the Wayback Machine
- ^ Lurie, John C.; Davenport, James R. A.; Hawley, Suzanne L.; Wilkinson, Tessa D.; Wisniewski, John P.; Kowalski, Adam F.; Hebb, Leslie (2015). "Kepler Flares III: Stellar Activity on GJ 1245A and B". The Astrophysical Journal. 800 (2): 95. arXiv: 1412.6109. Bibcode: 2015ApJ...800...95L. doi: 10.1088/0004-637X/800/2/95. S2CID 51773906.
- ^ Kholopov, P. N.; Kukarkina, N. P.; Perova, N. B. (1978). "63rd Name-List of Variable Stars". Information Bulletin on Variable Stars. 1414: 1. Bibcode: 1978IBVS.1414....1K.
- ^ a b Salama, Maïssa; Ou, James; et al. (September 2021). "Large Adaptive Optics Survey for Substellar Objects around Young, Nearby, Low-mass Stars with Robo-AO". The Astronomical Journal. 162 (3): 102. arXiv: 2105.13364. Bibcode: 2021AJ....162..102S. doi: 10.3847/1538-3881/ac0445.
Further reading
- Harrington, R. S.; Dahn, C. C.; Kallarakal, V. V.; Guetter, H. H.; Riepe, B. Y.; Walker, R. L.; Pier, J. R.; Vrba, F. J.; Luginbuhl, C. B.; Harris, H. C.; Ables, H. D. (1993). "U.S. Naval Observatory photographic parallaxes - List IX". Astronomical Journal. 105 (4): 1571–1580. Bibcode: 1993AJ....105.1571H. doi: 10.1086/116537.
- Henry, Todd J.; Subasavage, John P.; Brown, Misty A.; Beaulieu, Thomas D.; Jao, Wei-Chun; Hambly, Nigel C. (2004). "The Solar Neighborhood. X. New Nearby Stars in the Southern Sky and Accurate Photometric Distance Estimates for Red Dwarfs". The Astronomical Journal. 128 (5): 2460–2473. arXiv: astro-ph/0408240. Bibcode: 2004AJ....128.2460H. doi: 10.1086/425052. S2CID 15759789.
- Smart, R. L.; Ioannidis, G.; Jones, H. R. A.; Bucciarelli, B.; Lattanzi, M. G. (2010). "Cool dwarfs stars from the Torino Observatory Parallax Program". Astronomy and Astrophysics. 514: A84. arXiv: 1003.1465. Bibcode: 2010A&A...514A..84S. doi: 10.1051/0004-6361/200913424. S2CID 17961025.
- Dittmann, Jason A.; Irwin, Jonathan M.; Charbonneau, David; Berta-Thompson, Zachory K. (2014). "Trigonometric Parallaxes for 1507 Nearby Mid-to-late M Dwarfs". The Astrophysical Journal. 784 (2): 156. arXiv: 1312.3241. Bibcode: 2014ApJ...784..156D. doi: 10.1088/0004-637X/784/2/156. S2CID 18789867. Table with parallaxes.
External links
- http://jumk.de/astronomie/near-stars/v1581-cygni.shtml
- http://www.answers.com/topic/list-of-nearest-stars?cat=travel
- http://www.richweb.f9.co.uk/astro/nearby_stars.htm
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