HD 168443

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HD 168443
Observation data
Epoch 2000
Constellation
(pronunciation)
Serpens
Right ascension 18h 20m 04.11s
Declination -09° 35' 34.6"
Apparent magnitude (V) 6.92
Distance 123.5 ly
(37.88 pc)
Spectral type G5IV
Other designations
GJ 4052, BD-09°4692,
HIP 89844

HD 168443 is a yellow dwarf star of (spectral type G5) about the mass of our Sun. It is in the constellation of Serpens Cauda, 123 light years from our solar system. It is known to be orbited by one large planet and a brown dwarf.

Contents

[edit] HD 168443 b

HD 168443 b
Orbital elements
Semi-major axis a: 0.29 AU
Eccentricity e: 0.529 ± 0.02
Orbital period P: 58.116 ± 0.001 d
Inclination i:  ?°
Angular distance θ: 7.656 mas
Longitude of
periastron ω:
172.9°
Time of periastron τ: 2,451,616.36 ± 0.02 JD
Semi-amplitude K: 475.9 ± 1.6 m/s
Physical characteristics
Mass: >7.2 ± 0.4 MJ
Radius:  ? RJ
Density:  ? kg/
Gravity:  ? g
Temperature:  ? K
Discovery
Discovery date: 1998
Discovery site:
Detection method(s): Radial velocity
Discoverer(s): Butler, Marcy
Other catalogue

HD 168443 b is a planet seven times as massive as Jupiter. Given the high mass, this planet is likely to be a gas giant, or possibly a small brown dwarf depending on the orbital inclination. It orbits closer to its star than Mercury does to the Sun, and its surface temperature is likely to be very high.

[edit] HD 168443 c

HD 168443 c
Orbital elements
Semi-major axis a: 2.87 AU
Eccentricity e: 0.228 ± 0.005
Orbital period P: 1739.5 ± 3.98 d
Inclination i: 150°
Angular distance θ: 75.768 mas
Longitude of
periastron ω:
63°
Time of periastron τ: 2,452,015.5 ± 3.6 JD
Semi-amplitude K: 298.0 ± 1.2 m/s
Physical characteristics
Mass: 34 ± 12 MJ
Radius:  ? RJ
Density:  ? kg/
Gravity:  ? g
Temperature:  ? K
Discovery
Discovery date: 2001
Discovery site:
Detection method(s): Radial velocity
Discoverer(s): Butler, Marcy et al.
Udry, Mayor et al.
Other catalogue

HD 168443 c is a brown dwarf orbiting beyond the outer edge of the habitable zone of HD 168443. Radial velocity measurements give a minimum mass 17.1 times that of Jupiter. The best-fit astrometric solution using data from the Hipparcos mission gives an inclination of 150° and a mass 34 times that of Jupiter.

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