HD 142245

HD 142245 is a hierarchical triple star system about 318 light-years away.

HD 142245

Observation data Epoch J2000      Equinox J2000
Constellation	Serpens[1]
Right ascension	15h 52m 56.28008s[2]
Declination	+15° 25′ 50.5379″[2]
Apparent magnitude (V)	7.45[3]
Characteristics
Evolutionary stage	subgiant[4]
Spectral type	K0IV+M1[5]
Astrometry
Radial velocity (Rv)	6.92 km/s
Proper motion (μ)	RA: −57.312[2] mas/yr Dec.: −21.641[2] mas/yr
Parallax (π)	10.2374±0.0224 mas[2]
Distance	318.6 ± 0.7 ly (97.7 ± 0.2 pc)
Absolute magnitude (MV)	+2.27[1]
Orbit
Primary	HD 142245 A
Companion	HD 142245 BC
Semi-major axis (a)	2.5" (237 AU[6])
Details[7]
HD 142245 A
Mass	1.52±0.05[5] M☉
Radius	4.8±0.1[8] R☉
Luminosity	11.4[8] L☉
Surface gravity (log g)	3.21±0.14 cgs
Temperature	4,838±36[9] K
Metallicity	0.20±0.02[9]
Age	2.855±0.514 Gyr
HD 142245 BC
Mass	0.56[6] M☉
Other designations
BD+15 2925, Gaia DR2 1193193836691820032, HD 142245, HIP 77783, TYC 1496-1841-1, 2MASS J15525629+1525507[10]
Database references
SIMBAD	data

The primary subgiant star HD 142245 A belongs to the spectral class of K0. Its age is much younger than Sun`s at 2.855±0.514 billion years.^[9] The primary star is slightly enriched by heavy elements, having 160% of solar abundance.^[9]

In 2014, the co-moving binary stellar companion HD 142245 BC was detected. It consists of pair of red dwarf stars with composite spectral class M1, orbiting each other on 4 AU orbit.^[6]

No other stellar companions were found at projected separations from 5.48 to 153.34 AU around HD 142245 A.^[5]

Planetary system

In 2011 one superjovian planet HD 142245 A b on a mildly eccentric orbit around star HD 142245 A was discovered utilizing the radial velocity method.^[11]

The HD 142245 planetary system^[12]

Companion (in order from star)	Mass	Semimajor axis (AU)	Orbital period (days)	Eccentricity	Inclination	Radius
HD 142245 A b	≥1.9±0.2 MJ	2.77±0.09	1299±48	0.32	—	—