HD 171238

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HD 171238
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Sagittarius
Right ascension 18h 34m 43.67500s[1]
Declination –28° 04′ 20.3381″[1]
Apparent magnitude (V) 8.606[2]
Characteristics
Spectral type G8 V[3]
Apparent magnitude (B) 9.40
Apparent magnitude (J) 7.244[4]
Apparent magnitude (H) 6.868[4]
Apparent magnitude (K) 6.831[4]
B−V color index 0.74[5]
Astrometry
Radial velocity (Rv) 21.1[2] km/s
Proper motion (μ) RA: –29.46 ± 1.64[1] mas/yr
Dec.: –111.01 ± 1.05[1] mas/yr
Parallax (π) 19.89 ± 1.15[1] mas
Distance 164 ± 9 ly
(50 ± 3 pc)
Absolute magnitude (MV) 5.15[5]
Details
Mass 0.943 ± 0.033[5] M
Surface gravity (log g) 4.43 ± 0.04[5] cgs
Temperature 5467 ± 55[5] K
Metallicity 0.17 ± 0.007[5]
Rotational velocity (v sin i) 1.48[5] km/s
Age 4.92 ± 4.11[5] Gyr
Other designations
CD–28°14719, HD 171238, HIP 91085, PPM 268605, SAO 186998.
Database references
SIMBAD data
Exoplanet Archive data
Extrasolar Planets
Encyclopaedia
data

HD 171238 is a 9th magnitude G-type main sequence star located approximately 164 light years away in the constellation Sagittarius. This star is a little bit cooler, less massive, older, and more metallic than the Sun. In August 2009, it was announced that this star has a planet.[5]

The HD 171238 planetary system
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b ≥2.6 ± 0.15 MJ 2.54 ± 0.06 1523+40
−45
0.4+0.061
−0.065

See also[edit]

References[edit]

  1. ^ a b c d e van Leeuwen, Floor (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, arXiv:0708.1752v1, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357  Note: see VizieR catalogue I/311.
  2. ^ a b Nordström, B. et al. (May 2004), "The Geneva-Copenhagen survey of the Solar neighbourhood. Ages, metallicities, and kinematic properties of ˜14 000 F and G dwarfs", Astronomy and Astrophysics 418: 989–1019, arXiv:astro-ph/0405198, Bibcode:2004A&A...418..989N, doi:10.1051/0004-6361:20035959 
  3. ^ Houk, Nancy (1979), Michigan catalogue of two-dimensional spectral types for the HD stars 3, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode:1982MSS...C03....0H 
  4. ^ a b c Cutri, R. M. et al. (June 2003), 2MASS All Sky Catalog of point sources, NASA/IPAC, Bibcode:2003tmc..book.....C 
  5. ^ a b c d e f g h i Ségransan, D. et al. (2009). "The CORALIE survey for southern extrasolar planets. XVI. Discovery of a planetary system around HD 147018 and of two long period and massive planets orbiting HD 171238 and HD 204313". Astronomy & Astrophysics 511: A45. arXiv:0908.1479. Bibcode:2010A&A...511A..45S. doi:10.1051/0004-6361/200912136. 

Coordinates: Sky map 18h 34m 43.6733s, −28° 04′ 20.328″