HD 33541

HD 33541, also known as HR 1683, is a white-hued star located in the northern circumpolar constellation Camelopardalis. It has an apparent magnitude of 5.83,^[3] making it faintly visible to the naked eye. Gaia DR3 parallax measurements imply a distance of 358 light years^[2] and it is currently receding with a heliocentric radial velocity of 9.9 km/s.^[5] At its current distance HD 33541's brightness is diminished by 0.16 magnitudes due to interstellar extinction^[14] and it has an absolute magnitude of +0.58.^[1]

HD 33541

Location of HD 33541 on the map (circled)
Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Camelopardalis[1]
Right ascension	05h 18m 13.24213s[2]
Declination	+73° 16′ 05.1509″[2]
Apparent magnitude (V)	5.83±0.01[3]
Characteristics
Evolutionary stage	main sequence[2]
Spectral type	A0 V[4]
U−B color index	−0.12[3]
B−V color index	−0.04[3]
Astrometry
Radial velocity (Rv)	9.9±3.2[5] km/s
Proper motion (μ)	RA: −2.361 mas/yr[2] Dec.: −28.254 mas/yr[2]
Parallax (π)	9.0993±0.0488 mas[2]
Distance	358 ± 2 ly (109.9 ± 0.6 pc)
Absolute magnitude (MV)	+0.58[1]
Orbit[6]
Primary	HD 33541A
Companion	HD 33541B
Period (P)	20.8199180±0.0000458 d
Eccentricity (e)	0.245±0.006
Periastron epoch (T)	2,457,388.471+0.002 −0.003 JD
Argument of periastron (ω) (secondary)	108±1°
Semi-amplitude (K1) (primary)	39.3±0.3 km/s
Semi-amplitude (K2) (secondary)	38.0±0.3 km/s
Details
Mass	2.69±0.35[7] M☉
Radius	2.52±0.13[8] R☉
Luminosity	69.3±0.9[2] L☉
Surface gravity (log g)	4.09+0.07 −0.05[7] cgs
Temperature	11,200[9] K
Metallicity [Fe/H]	−0.15[10] dex
Rotational velocity (v sin i)	70[11] km/s
Age	300[12] Myr
Other designations
AG+73°141, BD+73°280, GC 6405, HD 33541, HIP 24732, HR 1683, SAO 5483[13]
Database references
SIMBAD	data

The object has a stellar classification of A0 V,^[4] indicating that it is an ordinary A-type main-sequence star. It has 2.69 times the mass of the Sun^[7] and 2.52 times the Sun's radius.^[8] It radiates 69.3 times the luminosity of the Sun^[2] from its photosphere at an effective temperature of 11,200 K.^[9] HD 33541 has an iron abundance 71% that of the Sun ([Fe/H] = −0.15)^[10] and it is estimated to be 300 million years old.^[12] The star spins modestly with a projected rotational velocity of 70 km/s.^[11]

HD 33541 was originally considered to be a solitary star.^[15] However, Abt & Morell (1995) suggested that HD 33541 may be a close binary with two components that each have rotational velocities of 10 km/s.^[16] A later paper gives the rotational velocity of the primary as 60 km/s and of the secondary 11 km/s.^[17] It is now considered to be a spectroscopic binary with a period of 20.8 hours and a somewhat eccentric orbit based on Gaia DR3 models.^[6]