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Kepler-68
Observation data; Epoch J2000 Equinox J2000
Constellation	Cygnus
Right ascension	19h 24m 07.76597s
Declination	+49° 02′ 24.9283″
Apparent magnitude (V)	10.08
Characteristics
Evolutionary stage	Main sequence
Spectral type	G1V
Astrometry
Radial velocity (Rv)	−20.50±0.23 km/s
Proper motion (μ)	RA: −7.305 mas/yr ; Dec.: −10.454 mas/yr
Parallax (π)	6.9298 ± 0.0100 mas
Distance	470.7 ± 0.7 ly ; (144.3 ± 0.2 pc)
Details
Mass	1.057+0.022; −0.020 M☉
Radius	1.2564±0.0084 R☉
Temperature	5847±75 K
Metallicity [Fe/H]	0.11±0.06 dex
Rotational velocity (v sin i)	2.4±0.5 km/s
Age	6.84+0.90; −1.04 Gyr
Other designations
	BD+48 2893, KOI-246, KIC 11295426, TYC 3551-189-1, GSC 03551-00189, 2MASS J19240775+4902249
Database references
SIMBAD	data
KIC	data

Kepler-68 is a Sun-like main sequence star located 471 light-years (144 parsecs) away in the constellation Cygnus. It is known to have at least four planets orbiting around it.^[3] The third planet has a mass similar to Jupiter but orbits within the habitable zone.^[5]

High resolution imaging observations of Kepler-68 carried out with the lucky imaging instrument AstraLux on the 2.2m telescope at Calar Alto Observatory detected a wide companion candidate approximately 11 arcseconds away. Comparing these observations to the 2MASS positions shows that the companions proper motion is consistent with it being bound to the Kepler-68 system, but further observations are needed to confirm this conclusion.^[6] Eleven arcseconds at the distance of Kepler-68 leads to a sky projected separation of approximately 1600 Astronomical units. A circular orbit at that distance would have a period of roughly 50,000 years.^[7]

Planetary system

Currently, four planets have been discovered to orbit around Kepler-68. The two innermost planets were discovered by the planetary transit method. Follow-up Doppler measurements helped to determine the mass of Kepler-68b and helped to discover Kepler-68d.^[5]^[8] There is an additional signal present in the radial velocity measurements indicating another body in the system at a period of greater than 10 years. The mass of this object was initially unknown and it could be either another planet or a stellar companion.^[7] In 2023, this fourth planet was confirmed, with a minimum mass about that of Saturn.^[3]

The Kepler-68 planetary system^[3]
Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
b	8.03±0.67 $M$ _🜨	0.06135±0.00043	5.39875259	<0.090	87.23+0.22 −0.17°	2.357±0.023 $R$ _🜨
c	<1.3 $M$ _🜨	0.09008±0.00063	9.605027	<0.099	87.071+0.087 −0.094°	0.979±0.019 $R$ _🜨
d	≥0.749±0.017 $M$ _J	1.469±0.010	632.62±1.03	0.102±0.016	—	—
e	≥0.272±0.032 $M$ _J	4.60+0.32 −0.16	3455+348 −169	0.33±0.11	—	—