HD 28204

HD 28204
Location of HD 28204 on the map (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Camelopardalis
Right ascension 04h 33m 30.68009s[1]
Declination +72° 31′ 42.9803″[1]
Apparent magnitude (V) 5.93±0.01[2]
Characteristics
Spectral type kA8 hF0 mF2[3]
U−B color index +0.16[4]
B−V color index +0.28[4]
Astrometry
Radial velocity (Rv)9.0±0.9[5] km/s
Proper motion (μ) RA: +30.055 mas/yr[1]
Dec.: −90.625 mas/yr[1]
Parallax (π)9.8596 ± 0.0214 mas[1]
Distance330.8 ± 0.7 ly
(101.4 ± 0.2 pc)
Absolute magnitude (MV)+0.91[6]
Orbit[7]
Period (P)4.1950 d
Eccentricity (e)0.040±0.029[8]
Inclination (i)28-43°
Periastron epoch (T)2,426,034.6450 JD
Argument of periastron (ω)
(secondary)		337±244[8]°
Semi-amplitude (K1)
(primary)		31.3 km/s
Details
Aa
Mass1.68[9] M☉
Radius3.48±0.18[10] R☉
Luminosity35.7±0.2[1] L☉
Surface gravity (log g)3.58+0.10
−0.06[11] cgs
Temperature7,320±157[12] K
Metallicity [Fe/H]−0.14[13] dex
Rotational velocity (v sin i)23±10[3] km/s
Age1.103[14] Gyr
Ab
Mass0.474[9] M☉
Other designations
AG+72°116, BD+72°227A, FK5 2333, GC 5478, HD 28204, HIP 21247, HR 1401, SAO 5238, ADS 3267 A, CCDM J04335+7232A, WDS J04335+7232A, TIC 103566595[15]
Database references
SIMBADdata

HD 28204, also designated as HR 1401, is a spectroscopic binary[16] located in the northern circumpolar constellation Camelopardalis. It has an apparent magnitude of 5.93,[2] making it faintly visible to the naked eye under ideal conditions. Gaia DR3 parallax measurements imply a distance of 331 light-years and it is currently receding with a heliocentric radial velocity of 9 km/s.[5] At its current distance, HD 28204's brightness is diminished by 0.18 magnitudes due to interstellar extinction and it has an absolute magnitude of +0.91.[6]

HD 28204 is a single-lined spectroscopic binary consisting of an Am star and an unseen companion, as the primary is the only one detectable in the spectrum. With a mass of 0.474 M☉,[9] the companion might be a K-type main-sequence star. Both stars take 4.2 days to revolve around each other in a nearly circular orbit, which is somewhat constrained.[7] HD 28204 has two optical companions: a 12th magnitude star located 39" away along a position angle of 257° and a 14th magnitude star located 27.3" along a position angle of 55°.[17]

The visible component has a stellar classification of kA8hF0mF2,[3] indicating that it is an Am star with the calcium K-lines of an A8 star, the hydrogen lines of a F0 star, and the metallic lines of a F2 star. It has 1.68 times the mass of the Sun[9] and an enlarged radius 3.48 times that of the Sun.[10] It radiates 35.7 times the luminosity of the Sun[1] from its photosphere at an effective temperature of 7,320 K,[12] giving it the typical white hue of an A-type star. It is slightly metal deficient with an iron abundance of [Fe/H] = −0.15 or 72% that of the Sun's.[13] Like many Am stars it spins slowly, having a projected rotational velocity of 23 km/s.[3]

  1. ^ a b c d e f Cite error: The named reference GaiaDR3 was invoked but never defined (see the help page).
  2. ^ a b Cite error: The named reference Tycho2000 was invoked but never defined (see the help page).
  3. ^ a b c d Cite error: The named reference Abt1995 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Oja1983 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Wilson1953 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference Luyten1936 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference Lucy1971 was invoked but never defined (see the help page).
  9. ^ a b c d Cite error: The named reference Kraicheva1980 was invoked but never defined (see the help page).
  10. ^ a b Cite error: The named reference Kervella2004 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Stassun2019 was invoked but never defined (see the help page).
  12. ^ a b Cite error: The named reference McDonald2017 was invoked but never defined (see the help page).
  13. ^ a b Cite error: The named reference Anders2019 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference Gontcharov2012 was invoked but never defined (see the help page).
  15. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  16. ^ Cite error: The named reference Pourbaix2004 was invoked but never defined (see the help page).
  17. ^ Cite error: The named reference Mason2001 was invoked but never defined (see the help page).