LHS 6343

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LHS 6343
Observation data
Epoch J2000      Equinox J2000
Constellation Lyra
Right ascension  19h 10m 14.354s[1]
Declination +46° 57′ 26.14″[1]
Apparent magnitude (V) 13.435
(13.88 / 14.63)[2]
Characteristics
LHS 6343 A
Spectral type M4V[3] / T[4]
B−V color index 1.57 ± 0.07[2]
LHS 6343 B
Spectral type M5V[3]
B−V color index 1.60 ± 0.07[2]
Astrometry
Proper motion (μ) RA: -76.59[5] mas/yr
Dec.: -176.78[5] mas/yr
Distance119.4 ± 3.6[2] ly
(36.6 ± 1.1[2] pc)
Orbit[6]
Period (P)12.7137941 ± 0.0000002 d
Semi-major axis (a)0.0797 ± 0.0008 AU
Eccentricity (e)0.030 ± 0.002
Inclination (i)90.45 ± 0.03°
Periastron epoch (T)JD 2455008.07259 ± 0.00001
Argument of periastron (ω)
(secondary)
320 ± 4°
Semi-amplitude (K1)
(primary)
9.69 ± 0.02 km/s
Details
LHS 6343 A
Mass0.358 ± 0.011[6] M
Radius0.373 ± 0.005[6] R
Surface gravity (log g)4.851 ± 0.008[2] cgs
Temperature3431 ± 21[6] K
Metallicity [Fe/H]0.04 ± 0.08[2] dex
Rotation13.137 ± 0.011[2]
LHS 6343 B
Mass0.292 ± 0.013[6] M
Radius0.394 ± 0.012[6] R
Temperature3354 ± 17[6] K
LHS 6343 C
Mass62.1 ± 1.2[6] MJup
Radius0.783 ± 0.011[6] RJup
Luminosity6.91×10−6[4] L
Surface gravity (log g)5.35 ± 0.02[2] cgs
Temperature1130 ± 50[4] K
Age5 ± 1[4] Gyr
Other designations
KOI-959, KIC 10002261, G 205-57, 2MASS J19101435+4657261
Database references
SIMBADLHS 6343
LHS 6343 A
LHS 6343 B
LHS 6343 C

LHS 6343 is a star system in the northern constellation of Lyra. It appears exceedingly faint with a combined apparent magnitude of 13.435.[2] Based on its stellar properties, the system is thought to be about 119.4 light-years (36.6 parsecs) away.[2]

LHS 6343 is a binary star with two red dwarfs, designated LHS 6343 A and B, respectively. A brown dwarf orbits LHS 6343 A at a close distance, and periodically transits it.[2] The brown dwarf, designated LHS 6343 C, is located within the brown dwarf desert, a zone around stars where very few brown dwarfs have been discovered.[2]

The system was in the field of view of the Kepler spacecraft,[2] and was monitored continuously for possible planets transiting the star, although the transits were found to be caused by LHS 6343 C.[2]

Properties[edit]

LHS 6343 is a visual binary. Both stars are red dwarf stars that are much less massive compared to the Sun—the primary is 36% the mass of the Sun and the secondary, 29.2% the mass of the Sun.[6] The two stars have been individually resolved using adaptive optics, showing an angular separation of 0.55″,[2] corresponding to a distance of about 20 astronomical units (AU).[7]

The brown dwarf LHS 6343 C orbits the primary star LHS 6343 A at a distance of only 0.0797 AU every 12.7 days.[6] It is about 5 billion years old, and models suggest the brown dwarf has a surface temperature of 1130 K.[4] The system hierarchy is similar to NLTT 41135, another red dwarf binary with a brown dwarf orbiting one of the stars.[2]

Possible planet[edit]

LHS 6343 may have a massive planet within the system.[7] In 2012, transit-timing variation was analyzed for any possible substellar companions that may be perturbing the brown dwarf from its normal orbit. Such an object would be less massive than Jupiter and its orbital period would be 3.5 to 8 times larger than that of the brown dwarf. However, the hypothetical perturber's existence has not been confirmed and warrants more observations of the system.[7]

The LHS 6343 planetary system[7]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b (unconfirmed) 0.1–1 MJ 44.45–101.6

References[edit]

  1. ^ a b Cutri, R. M.; et al. (2003). "2MASS All-Sky Catalog of Point Sources". VizieR On-line Data Catalog. Bibcode:2003yCat.2246....0C.
  2. ^ a b c d e f g h i j k l m n o p q Johnson, John Asher; Apps, Kevin; Gazak, J. Zachary; Crepp, Justin R.; Crossfield, Ian J.; Howard, Andrew W.; Marcy, Geoff W.; Morton, Timothy D.; Chubak, Carly; Isaacson, Howard (2011). "LHS 6343 C: A Transiting Field Brown Dwarf Discovered by The Kepler Mission". The Astrophysical Journal. 730 (2): 79. arXiv:1008.4141. Bibcode:2011ApJ...730...79J. doi:10.1088/0004-637X/730/2/79.
  3. ^ a b Herrero, E.; Lanza, A. F.; Ribas, I.; Jordi, C.; Morales, J. C. (2013). "Photospheric activity, rotation, and magnetic interaction in LHS 6343 A". Astronomy & Astrophysics. 553: A66. arXiv:1303.7106. Bibcode:2013A&A...553A..66H. doi:10.1051/0004-6361/201220518.
  4. ^ a b c d e Montet, Benjamin T.; Johnson, John Asher; Fortney, Jonathan J.; Desert, Jean-Michel (2016). "Benchmark Transiting Brown Dwarf LHS 6343 C: Spitzer Secondary Eclipse Observations Yield Brightness Temperature and Mid-T Spectral Class". The Astrophysical Journal. 822: L6. arXiv:1603.09343. Bibcode:2016ApJ...822L...6M. doi:10.3847/2041-8205/822/1/L6.
  5. ^ a b Lépine, Sébastien; Shara, Michael M. (2005). "A Catalog of Northern Stars with Annual Proper Motions Larger than 0."15 (LSPM-NORTH Catalog)". The Astronomical Journal. 129 (3): 1483. arXiv:astro-ph/0412070. Bibcode:2005AJ....129.1483L. doi:10.1086/427854.
  6. ^ a b c d e f g h i j k Montet, Benjamin T.; Johnson, John Asher; Muirhead, Philip S.; Villar, Ashley; Vassallo, Corinne; Baranec, Christoph; Law, Nicholas M.; Riddle, Reed; Marcy, Geoffrey W.; Howard, Andrew W.; Isaacson, Howard (2015). "Characterizing the Cool KOIs. VII. Refined Physical Properties of the Transiting Brown Dwarf LHS 6343 C". The Astrophysical Journal. 800 (2): 134. arXiv:1411.4047. Bibcode:2015ApJ...800..134M. doi:10.1088/0004-637X/800/2/134.
  7. ^ a b c d Oshagh, M.; Boué, G.; Haghighipour, N.; Montalto, M.; Figueira, P.; Santos, N. C. (2012). "Transit-timing measurements with the model-independent barycenter method: Application to the LHS 6343 system". Astronomy & Astrophysics. 540: A62. arXiv:1109.3722. Bibcode:2012A&A...540A..62O. doi:10.1051/0004-6361/201118102.

Further reading[edit]