HD 192263

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**HD 192263**
Observation data Equinox 2000
Constellation	Aquila
Right ascension	20^h 13^m 59.85^s
Declination	-0° 52' 0.76"
Apparent magnitude (V)	8.1
Distance	64.85 ly (19.89 pc)
Spectral type	K2V
Other designations
BD-01°3925, HIP 99711

HD 192263 is an 8th magnitude star in the constellation of Aquila. The spectral type of the star is K2 V, meaning that it is an orange dwarf, a type of star somewhat cooler and less luminous than our Sun. It is not visible to the unaided eye, but with good binoculars or small telescope it should be easy to spot.

Various companions for the star have been reported, but all of them are probably line-of-sight optical components or just spurious observations.

This star lies close to the equator.

In 1999 an extrasolar planet was announced orbiting the star.

[edit] HD 192263 b

**HD 192263 b**
Orbital elements

Semi-major axis a:	0.15 AU
Eccentricity e:	0
Orbital period P:	24.348 ± 0.005 d
Inclination i:	?°
Longitude of periastron ω:	?°
Time of periastron τ:	2,451,979.28 ± 0.08 JD
Physical characteristics
Mass:	>0.72 M_J
Radius:	? R_J
Density:	? kg/m³
Temperature:	? K
Discovery
Discovery date:	1999
Detection method(s):
Discoverer(s):	Santos, Mayor, Naef et al.

The planet, designated as HD 192263 b, is a gas giant with a mass at least about three quarters that of Jupiter. It orbits the star in a circular orbit completing one revolution in 24 days or so.

In 2002 the existence of the planet was questioned: The star was observed to have photometric brightness variations that have same period and velocities as the planet. The signal could come from those variations instead of the planet orbiting the star. Finally, in 2003 the planet was confirmed.