HD 181720

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HD 181720
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Sagittarius
Right ascension 19h 22m 52.99s[1]
Declination –32° 55′ 08.6″[1]
Apparent magnitude (V) 7.84[2]
Characteristics
Spectral type G1V[2]
Apparent magnitude (B) 8.44
Apparent magnitude (J) 6.652
Apparent magnitude (H) 6.346
Apparent magnitude (K) 6.294
V−R color index 0.599[2]
Astrometry
Radial velocity (Rv) –57.2 km/s
Proper motion (μ) RA: 88.03 ± 1.44[1] mas/yr
Dec.: –414.99 ± 0.90[1] mas/yr
Parallax (π) 17.22 ± 1.16[1] mas
Distance 190 ± 10 ly
(58 ± 4 pc)
Absolute magnitude (MV) 4.10[2]
Details
Mass 0.92[2] M
Radius 1.39[2] R
Luminosity 1.94[2] L
Surface gravity (log g) 4.24 ± 0.15[2] cgs
Temperature 5781 ± 18[2] K
Metallicity -0.53 ± 0.02[2]
Rotation 47 days
Rotational velocity (v sin i) 1.5[2] km/s
Other designations
CD–33°14164, GCRV 69331, HIP 95262, LTT 7666, NLTT 47718, PPM 298918, SAO 211218
Database references
SIMBAD data
Exoplanet Archive data
Extrasolar Planets
Encyclopaedia
data

HD 181720 is an 8th magnitude G-type main sequence star located approximately 190 light years away in the constellation Sagittarius. This star is larger, hotter, brighter, and less massive than our Sun. Also its metal content is three-tenths as much as the Sun. In 2009, a gas giant planet was found in orbit around the star.

The HD 181720 planetary system[2]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b ≥0.37 MJ 1.78 956 ± 14 0.26 ± 0.06

See also[edit]

References[edit]

Coordinates: Sky map 19h 22m 52.9859s, −32° 55′ 08.595″