HD 164427

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HD 164427

Observation data Epoch J2000.0
Constellation (pronunciation)	Telescopium
Right ascension	18h 04m 42.5963s
Declination	−59º 12' 34.4690″
Apparent magnitude (V)	6.89
Absolute magnitude (V)	3.93
Distance	127.6 ly (39.12 pc)
Spectral type	G0+V
Other designations
CD-59 6780 , HIP 88531, Gliese 700, SAO 245217

164427 is a star in Telescopium constellation with a brown dwarf companion discovered in 2001 taking place in Australia.

[edit] HD 164427 b

HD 164427 b

Extrasolar planet		List of extrasolar planets
Orbital elements
Semimajor axis	(a)	0.46 AU
Eccentricity	(e)	0.55
Orbital period	(P)	108.55 d
Angular distance	(θ)	11.76 mas
Longitude of periastron	(ω)	55.2°
Time of periastron	(T0)	2,451,189.3 JD
Semi-amplitude	(K)	1398.5 m/s
Physical characteristics
Mass	(m)	>46 MJ
Discovery information
Discovery date		2001
Discoverer(s)		Tinney et al.
Detection method		Doppler Spectroscopy
Discovery site		Australia
Discovery status		Published

HD 164427 b is a brown dwarf with a minimum mass of 46 times that of Jupiter. It orbits at nearly half an astronomical unit or Earth-to-Sun distance away from its star (HD 164427). The angular separation between a brown dwarf and a yellow dwarf as viewed from Earth is 11.76 milliarcseconds. It takes 108.55 Earth days to orbit eccentrically around HD 164427. It has a very high semi-amplitude of almost 1400 m/s, because this is a very massive object which exerts strong gravitational pull on its tugging star.

[edit] References

• Tinney et al. (2001). "First Results from the Anglo-Australian Planet Search: A Brown Dwarf Candidate and a 51 Peg-like Planet". The Astrophysical Journal 551 (1): 507–511. doi:10.1086/320097. 

[edit] External links

• HD 164427 -- Yellow Subgiant. Extrasolar Visions. Retrieved on December 21, 2007.
• HD 164427 B – Brown dwarf. Extrasolar Visions. Retrieved on December 21, 2007.
• NLTT 45831 -- High proper-motion Star. SIMBAD. Retrieved on December 21, 2007.