HD 194688

HD 194688, also designated as HR 7816, is a solitary star located in the northern constellation Delphinus, the dolphin. It has an apparent magnitude of 6.22,^[2] placing it near the limit for naked eye visibility. The object is located relatively far away at a distance of 886 light-years based on Gaia DR3 parallax measurements,^[1] but it is drifting closer with a heliocentric radial velocity of −17.12 km/s.^[5] At its current distance, HD 196488's brightness is diminished due to an interstellar extinction of 0.17 magnitudes^[11] and it has an absolute visual magnitude of −1.19.^[6]

HD 194688

Location of HD 194688 on the map (circled)
Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Delphinus
Right ascension	20h 26m 23.15478s[1]
Declination	+17° 18′ 56.0140″[1]
Apparent magnitude (V)	6.22±0.01[2]
Characteristics
Spectral type	K0[3]
B−V color index	+1.01[4]
Astrometry
Radial velocity (Rv)	−17.12±0.27[5] km/s
Proper motion (μ)	RA: +5.397 mas/yr[1] Dec.: −5.426 mas/yr[1]
Parallax (π)	3.6827±0.0184 mas[1]
Distance	886 ± 4 ly (272 ± 1 pc)
Absolute magnitude (MV)	−1.19[6]
Details
Mass	1.57[7] M☉
Radius	21.58[8] R☉
Luminosity	258+3 −2[1] L☉
Surface gravity (log g)	1.91[7] cgs
Temperature	4,995±122[9] K
Metallicity [Fe/H]	−0.13[7] dex
Other designations
AG+17°2201, BD+16°4259, FK5 3635, GC 28435, HD 194688, HIP 100807, HR 7816, SAO 106101, TIC 305526917[10]
Database references
SIMBAD	data

HD 194688 has a simple stellar classification of K0,^[3] indicating that it is an early K-type star. It has 1.57 times the mass of the Sun^[7] and an enlarged radius 21.58 times that of the Sun.^[8] It radiates 258 times the luminosity of the Sun^[1] from its photosphere at an effective temperature of 4,995 K,^[9] giving it an orangish-yellow hue when viewed in the night sky. The large radius and high luminosity suggests that HD 194688 may be an evolved giant star. It is slightly metal-deficient with an iron abundance 74.1% that of the Sun's.^[7]