HD 169830

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**HD 169830**
Observation data Equinox 2000
Constellation	Sagittarius
Right ascension	18^h 27^m 49.4838^s
Declination	-29° 49' 00.715"
Apparent magnitude (V)	5.911
Distance	118.46 ly (36.32 pc)
Spectral type	F9V
Other designations
HR 6907,HIP 90485

HD 169830 is a yellow dwarf star (spectral type F9V) in the constellation of Sagittarius, 118.46 light years from our solar system. It is known to be orbited by two large planets.

1 HD 169830 b
2 HD 169830 c
3 See also
4 References
5 External links

[edit] HD 169830 b

**HD 169830 b**
Orbital elements

Semi-major axis a:	0.81 AU
Eccentricity e:	0.31 ± 0.01
Orbital period P:	225.62 ± 0.22 d
Inclination i:	?°
Longitude of periastron ω:	148 ± 2°
Time of periastron τ:	2,451,923 ± 1 JD
Physical characteristics
Mass:	>2.88 M_J
Radius:	? R_J
Density:	? kg/m³
Temperature:	? K
Discovery
Discovery date:	2000
Detection method(s):	Radial velocity
Discoverer(s):	Mayor, Udry et al.

HD 169830 b is an extrasolar planet three times the mass of Jupiter. It orbits close to the star, and the temperature of its cloud tops is unduobtedly very high, as a result. Due to its enormous mass, it is most likely a gas giant planet, akin to Jupiter and Saturn in our own solar system.

[edit] HD 169830 c

**HD 169830 c**
Orbital elements

Semi-major axis a:	3.60 AU
Eccentricity e:	0.33 ± 0.02
Orbital period P:	2102 ± 264 d
Inclination i:	?°
Longitude of periastron ω:	252 ± 8°
Time of periastron τ:	2,452,516 ± 25 JD
Physical characteristics
Mass:	>4.04 M_J
Radius:	? R_J
Density:	? kg/m³
Temperature:	? K
Discovery
Discovery date:	2003
Detection method(s):	Radial velocity
Discoverer(s):	Mayor, Udry et al.

HD 169830 c is an extrasolar planet, most likely a gas giant, four times as massive as Jupiter. Although its apperence is unknown, speculation suggests that the planet is white in apperence, due to water clouds similar to those in our own atmosphere. Its orbit is nearly circular, with a period (year) of 1487 days. The planet orbits in the middle of the star's habitabal zone; therefor, if any moons orbit the planet, they could houbor life.

[edit] See also

List of stars with confirmed extrasolar planets

[edit] References

Naef et al. (2001). "The CORALIE survey for southern extrasolar planets V. 3 new extrasolar planets". Astronomy and Astrophysics 375: 205-218.
Mayor et al. (2004). "The CORALIE survey for southern extra-solar planets XII. Orbital solutions for 16 extra-solar planets discovered with CORALIE". Astronomy and Astrophysics 415: 391-402.

[edit] External links

HD 169830. SIMBAD. Retrieved on 14 April 2006.
Notes for star HD 169830. The Extrasolar Planets Encyclopaedia. Retrieved on 14 April 2006.
John Whatmough. HD 169830. Extrasolar Visions. Retrieved on 14 April 2006.