HD 199223

HD 199223 (HR 8010) is a double star in the equatorial constellation Delphinus. However, the system was originally in Equuleus prior to the creation of official IAU constellation borders.^[14] The components have a separation of 2″ at a position angle of 282° as of 2016.^[15] They have apparent magnitudes of 6.34 and 7.49 and distances of 354 and 359 light years respectively. The system is drifting closer with a radial velocity of −33 km/s.

Apparentmagnitude(V)6.34±0.01^[3]

Apparentmagnitude(V)7.49±0.01^[3]

Evolutionarystagered giant branch^[2]

SpectraltypeG8 III/IV^[5]

Quick facts Observation data Epoch J2000 Equinox J2000, Apparent magnitude (V) ...

HD 199223

Location of HD 199223 (circled)
Observation data Epoch J2000      Equinox J2000
Constellation	Delphinus[1]
A
Right ascension	20h 55m 40.6778s[2]
Declination	+04° 31′ 57.799″[2]
Apparent magnitude (V)	6.34±0.01[3]
B
Right ascension	20h 55m 40.5439s[4]
Declination	+04° 31′ 58.227″[4]
Apparent magnitude (V)	7.49±0.01[3]
Characteristics
A
Evolutionary stage	red giant branch[2]
Spectral type	G8 III/IV[5]
U−B color index	+0.49[6]
B−V color index	+0.82[6]
B
Spectral type	F/G[7]
Astrometry
Radial velocity (Rv)	−32.6±0.4[8] km/s
Absolute magnitude (MV)	+0.33[1]
A
Proper motion (μ)	RA: +60.413[2] mas/yr Dec.: +10.949[2] mas/yr
Parallax (π)	9.2067±0.0354 mas[2]
Distance	354 ± 1 ly (108.6 ± 0.4 pc)
B
Proper motion (μ)	RA: +60.315[4] mas/yr Dec.: +9.758[4] mas/yr
Parallax (π)	9.0757±0.0758 mas[4]
Distance	359 ± 3 ly (110.2 ± 0.9 pc)
Details
A
Mass	1.63[9] M☉
Radius	7.71[10] R☉
Luminosity	36.5[2] L☉
Surface gravity (log g)	2.75[9] cgs
Temperature	4,830[2] K
Metallicity [Fe/H]	0.16[9] dex
Rotational velocity (v sin i)	<1[11] km/s
Age	557[2] Myr
B
Mass	1.36[10] M☉
Radius	2.32[10] R☉
Luminosity	9.04[10] L☉
Surface gravity (log g)	3.84[10] cgs
Temperature	6,572[10] K
Metallicity [Fe/H]	−0.2[12] dex
Other designations
1 G. Equulei, AG+04°2834, BD+03°4461, GC 29200, HD 199223, HIP 103301, HR 8010, SAO 126373, WDS J20557+0432[13]
Database references
SIMBAD	The system
	A
	B

Close

The brighter component has a stellar classification of G8 III/IV,^[5] indicating that it is a G-type star with the blended luminosity class of a giant star and a subgiant. It has 163% of the mass of the Sun^[9] and an enlarged radius of 7.71 R_☉.^[10] It shines at 36.5 times the luminosity of the Sun^[2] from its photosphere at an effective temperature of 4,830 K,^[2] giving it a yellow glow. HD 199223A's iron abundance is 135% that of the Sun^[9] and it spins modestly with a projected rotational velocity less than 1 km/s.^[11]

As for the dimmer one, it is classified as an F/G star,^[7] and is calculated to be an F-type subgiant.^{[citation needed]} It has 136% of the mass of the Sun and 2.3 times its radius.^[10] It radiates with a luminosity of 9.04 L_☉ from its photosphere at an effective temperature of 6,572 K,^[10] giving it a yellow white glow.