Kepler-65

Kepler-65 is a subgiant star slightly more massive than the Sun and has at least four planets.

Kepler-65

Observation data Epoch J2000      Equinox J2000
Constellation	Lyra[1]
Right ascension	19h 14m 45.2916s[2]
Declination	+41° 09′ 04.210″[2]
Apparent magnitude (V)	11.018
Characteristics
Evolutionary stage	Subgiant
Spectral type	F6IV
Astrometry
Proper motion (μ)	RA: 1.256(14) mas/yr[2] Dec.: −14.388(12) mas/yr[2]
Parallax (π)	3.3184±0.0108 mas[2]
Distance	983 ± 3 ly (301.4 ± 1.0 pc)
Details
Mass	1.25 M☉
Radius	1.41 R☉
Temperature	6211 K
Metallicity [Fe/H]	+0.17 dex
Rotation	7.911±0.155 days[3]
Other designations
KOI-85, KIC 5866724, TYC 3125-976-1, GSC 03125-00976, 2MASS J19144528+4109042[4]
Database references
SIMBAD	data
KIC	data

Planetary system

Three transiting planets were announced in 2013. A fourth non-transiting planet was discovered using radial velocity measurements in 2019.^[5] The first three planets orbit very close to their star. Initial follow-up radial velocity measurements provided data too noisy to constrain the mass of planets.^[6] Follow-up transit-timing variation analysis helped to measure the mass of Kepler-65d which revealed that it has significantly lower density than Earth.^[7]

Size comparison of the three planets of Kepler 65 with a known radius (artistic concept) with Earth

The Kepler-65 planetary system^[5]

Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
b	2.4+2.4 −1.6 M🜨	0.035	2.1549209+0.0000086 −0.0000074	0.028+0.031 −0.02	92.2+1.3 −1.4°	1.444+0.037 −0.031 R🜨
c	5.4±1.7 M🜨	0.068	5.859697+0.000093 −0.000099	0.02+0.022 −0.013	92.33+0.29 −0.26°	2.623+0.066 −0.056 R🜨
d	4.14+0.79 −0.80 M🜨	0.084	8.13167+0.00024 −0.00021	0.014+0.016 −0.010	92.35+0.18 −0.16°	1.587+0.040 −0.035 R🜨
e	200+200 −50 M🜨	—	258.8+1.5 −1.3	0.283+0.064 −0.071	127.0+27.0 −25.0°	—

External links

• Kepler-65 System
• Kepler-65, The Open Exoplanet Catalogue