HD 23523

HD 23523 (HR 1158) is a binary star^[11] located in the northern circumpolar constellation Camelopardalis. It has a combined apparent magnitude of 5.82,^[3] making it faintly visible to the naked eye under ideal conditions. When resolved, the primary has an apparent magnitude of 6.31 while the secondary has a magntiude of 7.11.^[4] The system is located relatively close at a distance of about 234 light-years based on Gaia DR3 parallax measurements^[2] and it currently drifting closer with a somewhat heliocentric radial velocity of −9.6 km/s.^[7] At its current distance, HD 23523's combined brightness is diminished by 0.16 magnitudes due to interstellar extinction^[12] and it has a combined absolute magnitude of +1.55.^[1]

HD 23523

Location of HD 23523 on the map (circled)
Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Camelopardalis[1]
Right ascension	03h 49m 36.58592s[2]
Declination	+63° 17′ 49.0518″[2]
Apparent magnitude (V)	5.82[3] (6.31 + 7.11)[4]
Characteristics
Spectral type	A5 Vn[5]
B−V color index	+0.18[6]
Astrometry
Radial velocity (Rv)	−9.6±3.4[7] km/s
Proper motion (μ)	RA: −11.630 mas/yr[2] Dec.: −61.457 mas/yr[2]
Parallax (π)	13.9498±0.3245 mas[2]
Distance	234 ± 5 ly (72 ± 2 pc)
Absolute magnitude (MV)	+1.55[1] (combined)
Orbit[8]
Primary	HD 23523A[4]
Companion	HD 23523B[4]
Period (P)	10.180±0.509 yr
Semi-major axis (a)	0.1020±0.0031″
Eccentricity (e)	0.441
Details
A
Mass	1.75 or 1.81[9] M☉
B
Mass	1.64 or 1.51[9] M☉
Other designations
Moaï 1, AG+63°280, BD+62°612, GC 4560, HD 23523, HIP 17891, HR 1158, SAO 12917, WDS J03496+6318AB[10]
Database references
SIMBAD	data

The system was first discovered to be a double star in 1996 by Marcel Carbillet and colleagues after speckle interferometry observations.^[13] The stars are only about a tenth of an arcsecond apart,^[4] making observing their individual properties difficult. The discovery paper suggested that the two components might be equal based on the dynamical mass.^[13] Overall, HD 23523 has a stellar classification of A5 Vn,^[5] indicating that it is an A-type main-sequence star with broad or nebulous absorption lines due to rapid rotation. The primary has a mass either 1.75 or 1.81 times the mass of the Sun while the companion has a mass 1.64 or 1.51 times that of the Sun,^[9] depending on the approach.