astro.wikisort.org - Star

Kepler-421 (KOI-1274 A) is a yellow main sequence star, being of spectral class G7V. Orange star of spectral class K9V (KOI-1274 B), projected on sky plane just 1.085″ away, is not physically associated to it.[3] The distance to star KOI-1274 A is approximately 1150 light-years, and to KOI-1274 B is about 1900 light-years.

Kepler-421

Observation data Epoch J2000      Equinox J2000
Constellation	Lyra
Right ascension	18h 53m 01.6406s[1]
Declination	45° 5′ 15.9725″[1]
Apparent magnitude (V)	13.56±0.04[2]
Characteristics
Evolutionary stage	main sequence
Spectral type	G7V or K9V[3]
Astrometry
Proper motion (μ)	RA: −4.010±0.032[1] mas/yr Dec.: −20.398±0.037[1] mas/yr
Parallax (π)	2.8401 ± 0.0166 mas[1]
Distance	1,148 ± 7 ly (352 ± 2 pc)
Details
Mass	0.76[4] M☉
Radius	0.83+0.04 −0.03[5] R☉
Luminosity	0.451[1] L☉
Surface gravity (log g)	4.54[4] cgs
Temperature	5,308±50[2] K
Metallicity [Fe/H]	−0.25±0.08[2] dex
Rotation	28.5±0.3 d[2]
Rotational velocity (v sin i)	1.5±0.5[4] km/s
Age	14.38[4] Gyr
Other designations
Gaia DR2 2106891671567353728, KOI-1274, KIC 8800954, 2MASS J18530163+4505159[6]
Database references
SIMBAD	data
KIC	data

Planetary system

Kepler-421 (either KOI-1274 A or KOI-1274 B) has an exoplanet (Kepler-421b), which is notable for its position near the snow line.[7]

The Kepler-421 planetary system[5][8]

Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
b	—	1.219+0.089 −0.106	704.20±0.01	0.041+0.095 −0.034	89.965+0.024 −0.031°	0.411+0.021 −0.016 RJ

References

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