ADS 9731

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ADS 9731
Observation data
Epoch       Equinox J2000
Constellation Corona Borealis
Right ascension 15h 38m 12.91478s [1]
Declination +36° 14′ 48.5597″ [1]
Apparent magnitude (V) 6.9 (total)
Characteristics
Spectral type F4V, F5V, G4V, F3V, F7V, M3V? [2]
Astrometry
Parallax (π) 9.07 ± 5.48 mas
Distance approx. 400 ly
(approx. 110 pc)
Orbit
Other designations
BD+36 2626, CCDM J15382+3615AB, HD 329691, WDS J15382+3615AB
Database references
SIMBAD data

ADS 9731 is a star system that consists of six stars. Four of the stars are visually separate in the sky, forming a visual star system, which was resolved using adaptive optics in 1995.[3] Two of these stars were themselves found to be spectroscopic binaries in 1998, resulting in a total of six known stars in the system.[2] It is one of very few multiple star systems known to have at least six members.

The combined light from the whole system results in an integrated V magnitude of 6.9. The parallax measured by the Hipparcos satellite indicates that the system is relatively nearby at around 110 parsecs (360 light-years) from the Sun.[1] However, this distance is highly uncertain because the multiple stars in the system prevented Hipparcos from accurately measuring the parallax; the system may instead be at a distance of about 200 pc (650 ly).[4]

The star system has been considered as a possible target for direct imaging searches for exoplanets,[5] but no planets have yet been detected in the system.

References[edit]

  1. ^ a b c Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. 
  2. ^ a b Tokovinin, A. A.; Shatskii, N. I.; Magnitskii, A. K. (1998). "ADS 9731: A new sextuple system". Astronomy Letters 24: 795. Bibcode:1998PAZh...24..918T. 
  3. ^ Drummond, Jack D.; Christou, Julian C.; Fugate, Robert Q. (1995). "Full Adaptive Optics Images of ADS 9731 and MU Cassiopeiae: Orbits and Masses". Astrophysical Journal 450: 380. Bibcode:1995ApJ...450..380D. doi:10.1086/176148. 
  4. ^ Fabricius, C.; Makarov, V. V. (2000). "Hipparcos astrometry for 257 stars using Tycho-2 data". Astronomy and Astrophysics Supplement Series 144: 45. Bibcode:2000A&AS..144...45F. doi:10.1051/aas:2000198. 
  5. ^ Janson, M. (2010). "The relevance of prior inclination determination for direct imaging of Earth-like planets". Monthly Notices of the Royal Astronomical Society 408: 514. arXiv:1006.2941. Bibcode:2010MNRAS.408..514J. doi:10.1111/j.1365-2966.2010.17135.x.