OGLE-2005-BLG-169L

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**OGLE-2005-BLG-169L**
Observation data Epoch J2000.0
Constellation	Sagittarius
Right ascension	18^h 06^m 05^s
Declination	-30° 43' 57"
Apparent magnitude (V)	+19.4
Distance	8,800 ly (2,700 pc)
Spectral type	M?
Other designations
EWS 2005-BLG-169L

OGLE-2005-BLG-169L is a star about 2,700 parsecs away in the constellation Sagittarius. If it is a main sequence star, then it is most likely a red dwarf with about half of the mass of the Sun. Other possibilities are a white dwarf star, or (less likely) a neutron star or black hole.

In 2006, an extrasolar planet was detected around this star.

[edit] OGLE-2005-BLG-169Lb

**OGLE-2005-BLG-169Lb**
Microlensing parameters
Extrasolar planet		Lists of extrasolar planets
Observed separation	(d)	2.7 AU
Mass ratio	(q)	8.6×10^-5
Impact parameter	(u₀)	1.24 R_Einstein
Einstein ring crossing time	(t_E)	42.27 d
Time of closest approach	(t₀)	2,453,491.88 JD
Position angle	(φ)	117.0°
Physical characteristics
Mass	(m)	0.041 M_J (13 M_E)
Radius	(r)	? R_J
Density	(ρ)	? kg/m³
Temperature	(T)	~70 K
Discovery information
Discovery date		2006
Discoverer(s)		MicroFUN, PLANET/RoboNet, OGLE
Detection method		Gravitational microlensing
Discovery status		Confirmed

OGLE-2005-BLG-169Lb is a planet discovered by the OGLE project using the gravitational microlensing method. Based on a most likely mass for the host star of 0.49 solar masses, the planet has a mass of 13 times that of Earth. Its mass and estimated temperature are close to those of Uranus. It is speculated that this planet may either be an ice giant like Uranus, or a "naked super-Earth" with a solid icy or rocky surface.