Astronomy:HD 196885

From HandWiki
Short description: Multiple star system in the constellation Delphinus
HD 196885
Location of HD 196885 (circled in red)
Observation data
Equinox J2000.0]] (ICRS)
Constellation Delphinus[1]
Right ascension  20h 39m 51.87484s[2]
Declination +11° 14′ 58.7002″[2]
Apparent magnitude (V) 6.39[1]
Characteristics
Evolutionary stage main sequence[2]
Spectral type F8V[3] + M1±1V[4]
B−V color index 0.559±0.006[1]
Astrometry
Radial velocity (Rv)−30.13±0.09[1] km/s
Proper motion (μ) RA: +71.915[2] mas/yr
Dec.: +89.318[2] mas/yr
Parallax (π)29.4076 ± 0.0272[2] mas
Distance110.9 ± 0.1 ly
(34.00 ± 0.03 pc)
Absolute magnitude (MV)3.76[1]
Orbit[5]: 7 
PrimaryHD 196885 A
CompanionHD 196886 B
Period (P)69.045+0.533
−0.111 yr
Semi-major axis (a)19.778+0.108
−0.019 astronomical unit|AU
Eccentricity (e)0.417+0.001
−0.004
Inclination (i)120.427°
Longitude of the node (Ω)79.150°
Periastron epoch (T)1982.886 AD
Argument of periastron (ω)
(secondary)		231.464°
Details[5]
A
Mass1.3±0.1 M☉
Radius1.35±0.10[6] R☉
Luminosity2.611±0.007[2] L☉
Surface gravity (log g)4.46±0.02 cgs
Temperature6,340±39 K
Metallicity [Fe/H]+0.29±0.05 dex
Rotation15 days[7]
Rotational velocity (v sin i)7.3±1.5[7] km/s
Age1.5—3.5 Gyr
B
Mass0.45±0.01 M☉
Other designations
BD+10°4351, GC 28784, HD 196885, HIP 101966, HR 7907, SAO 106360, WDS J20399+1115, GSC 01092-01778, 2MASS J20395188+1114588[8]
Database references
SIMBADdata
Exoplanet Archivedata

HD 196885 is a binary star system in the northern constellation of Delphinus. It comprises a pair of stars, HD 196885 A and HD 196885 B, on a 69-year eccentric orbit. The primary star has one known planet.[5]

Stellar properties

HD 196885 A (center) and B (top left) imaged by SPHERE

The primary star is near the lower limit of visibility to the naked eye with an apparent visual magnitude of 6.39.[1] It is located at a distance of 110.9 light-years from the Sun.[2] It is drifting closer with a radial velocity of −30 km/s, and is expected to come to within 52.5 light-years in 836,000 years.[1]

The secondary, component B, is a red dwarf star separated by 0.6 arcseconds from the primary star that was discovered in 2006 with NaCo at VLT.[9][4] It has a class in the range M1V to M3V[4] with 51% of the Sun's mass.[5]

The star BD+10 4351B, located 192 arcseconds away from HD 196885, was once thought to be a possible third component of the system,[10] but Gaia astrometry shows a smaller parallax, indicating that it is an unrelated background star.[11]

Planetary system

In 2004, an exoplanet, HD 196885 Ab, was announced to be orbiting the star HD 196885 A in a 386-day orbit.[12] Follow-up work published in 2008 did not confirm the original candidate but instead found evidence of a planet in a 3.63 years orbit.[7] Perturbation by the secondary star in this system may have driven the planet into a high inclination orbit.[13] The planetary existence was confirmed and parameters were refined by 2022.[5]

The HD 196885 planetary system[5]: 7 
Companion
(in order from star) 		Mass Semimajor axis
(AU) 		Orbital period
(years) 		Eccentricity Inclination Radius
b 3.394+0.702
−0.264 MJ 		2.383+0.002
−0.004 		3.485+0.001
−0.016 		0.444+0.013
−0.005 		143.041+6.572
−4.582° 		—

See also

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode: 2012AstL...38..331A  XHIP record for this object at VizieR.
  2. ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 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.
  3. ↑ Gray, R. O. et al. (2001), "The Physical Basis of Luminosity Classification in the Late A-, F-, and Early G-Type Stars. I. Precise Spectral Types for 372 Stars", The Astronomical Journal 121 (4): 2148, doi:10.1086/319956, Bibcode: 2001AJ....121.2148G 
  4. ↑ 4.0 4.1 4.2 Chauvin, G. et al. (2007). "Characterization of the long-period companions of the exoplanet host stars: HD 196885, HD 1237 and HD 27442". Astronomy and Astrophysics 475 (2): 723–727. doi:10.1051/0004-6361:20067046. Bibcode: 2007A&A...475..723C. 
  5. ↑ 5.0 5.1 5.2 5.3 5.4 5.5 Chauvin, G.; Videla, M. et al. (July 2023). "Chasing extreme planetary architectures. I. HD 196885 Ab, a super-Jupiter dancing with two stars?". Astronomy & Astrophysics 675: A114. doi:10.1051/0004-6361/202244502. Bibcode: 2023A&A...675A.114C. 
  6. ↑ Ghezzi, L. et al. (September 2010). "Stellar Parameters and Metallicities of Stars Hosting Jovian and Neptunian Mass Planets: A Possible Dependence of Planetary Mass on Metallicity". The Astrophysical Journal 720 (2): 1290–1302. doi:10.1088/0004-637X/720/2/1290. Bibcode: 2010ApJ...720.1290G. 
  7. ↑ 7.0 7.1 7.2 Correia, A. C. M. et al. (2008). "The ELODIE survey for northern extra-solar planets. IV. HD 196885, a close binary star with a 3.7-year planet". Astronomy and Astrophysics 479 (1): 271–275. doi:10.1051/0004-6361:20078908. Bibcode: 2008A&A...479..271C. 
  8. ↑ "HD 196885". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+196885. 
  9. ↑ Chauvin, G. et al. (2006). "Probing long-period companions to planetary hosts. VLT and CFHT near infrared coronographic imaging surveys". Astronomy and Astrophysics 456 (3): 1165–1172. doi:10.1051/0004-6361:20054709. Bibcode: 2006A&A...456.1165C. 
  10. ↑ "HD 196885 A page". Geneva Observatory. http://obswww.unige.ch/exoplanets/hd196885A.html. Retrieved 2008-08-19. 
  11. ↑ "TYC 1096-637-1". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=TYC+1096-637-1. 
  12. ↑ "The Planet Around HD 196885". California & Carnegie Planet Search Team (Internet Archive link). Archived from the original on 2004-12-27. https://web.archive.org/web/20041227061730/http://exoplanets.org/esp/hd196885/hd196885.shtml. Retrieved 2008-08-19. 
  13. ↑ Satyal, S.; Hinse, T. C.; Quarles, B.; Noyola, J. P. (September 2014). "Chaotic dynamics of the planet in HD 196885 AB". Monthly Notices of the Royal Astronomical Society 443 (2): 1310–1318. doi:10.1093/mnras/stu1221. Bibcode: 2014MNRAS.443.1310S. 

Coordinates: Sky map 20h 39m 51.8756s, +11° 14′ 58.737″



Retrieved from "https://handwiki.org/wiki/index.php?title=Astronomy:HD_196885&oldid=4214974"