Kepler-25

Kepler-25 is a star in the northern constellation of Lyra.^[1] It is slightly larger and more massive than the Sun, with a luminosity 21⁄2 times that of the Sun.^[5] With an apparent visual magnitude of 10.6,^[3] this star is too faint to be seen with the naked eye.

Kepler-25

Observation data Epoch J2000      Equinox J2000
Constellation	Lyra[1]
Right ascension	19h 06m 33.2141s[2]
Declination	+39° 29′ 16.359″[2]
Apparent magnitude (V)	10.623±0.053[3]
Characteristics
Spectral type	F[4]
Apparent magnitude (B)	11.337±0.016[3]
Variable type	Planetary transit variable
Astrometry
Proper motion (μ)	RA: −0.303(14) mas/yr[2] Dec.: 6.109(13) mas/yr[2]
Parallax (π)	4.1456±0.0113 mas[2]
Distance	787 ± 2 ly (241.2 ± 0.7 pc)
Details
Mass	1.159+0.040 −0.051[5] M☉
Radius	1.297±0.015[5] R☉
Luminosity	2.406+0.126 −0.128[5] L☉
Surface gravity (log g)	4.275+0.007 −0.008[5] cgs
Temperature	6270±79[6] K
Metallicity [Fe/H]	−0.05±0.10[6] dex
Rotation	23.147±0.039 days[7]
Rotational velocity (v sin i)	9.5[8] km/s
Age	3.45+0.81 −0.72[5] Gyr
Other designations
Gaia DR2 2100451630105041152, KOI-244, KIC 4349452, TYC 3124-1264-1, 2MASS J19063321+3929164[9]
Database references
SIMBAD	data
KIC	data

Planetary system

In 2011, two candidate planets were found transiting this star by the Kepler space telescope.^[10] These planets are very close to yet not lie in the 1:2 orbital resonance to each other, indicating the absence of other planetary objects in the inner part of the planetary systems.^[11] These planets were confirmed through transit-timing variation method.^[12] A third planet was discovered through follow-up radial velocity measurements and was confirmed in January 2014.^[8]

The plane of planetary orbits is well aligned with the equatorial plane of the star, misalignment angle equal to 7±8°^[13]

The Kepler-25 planetary system^[14][4]

Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
b	8.7+2.5 −2.3 M🜨	0.068	6.238297±0.000017	0.0029+0.0023 −0.0017	92.827+0.084 −0.083°	2.748+0.038 −0.035 R🜨
c	15.2+1.3 −1.6 M🜨	0.11	12.7207±0.0001	0.0061+0.0049 −0.0041	92.764+0.042 −0.039°	5.217+0.070 −0.065 R🜨
d	71.9±9.8 M🜨	—	122.4+0.0 −0.7	0.13+0.13 −0.09	—	—