HD 22764

HD 22764
Location of HD 22764 on the map (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Camelopardalis
Right ascension 03h 42m 42.73699s[1]
Declination +59° 58′ 09.8029″[1]
Apparent magnitude (V) 5.78[2]
Characteristics
Spectral type K3.5 IIIb + G[3]
U−B color index +1.78[2]
B−V color index +1.76[2]
R−I color index +1.02[2]
Astrometry
Radial velocity (Rv)−12.53±0.26[4] km/s
Proper motion (μ) RA: −2.124 mas/yr[1]
Dec.: +2.342 mas/yr[1]
Parallax (π)1.8433 ± 0.0671 mas[1]
Distance1,770 ± 60 ly
(540 ± 20 pc)
Absolute magnitude (MV)−4.47[5]
Absolute bolometric
magnitude (Mbol)		−4.52±0.30[6]
Details
Mass2.86[7] or 6.8±1[8] M☉
Radius167±8[9] R☉
Luminosity3,342±221[10] L☉
Surface gravity (log g)1.08 or 1.41[11] cgs
Temperature3,928±170[6] K
Metallicity [Fe/H]−0.19[12] dex
Rotational velocity (v sin i)<1.9[13] km/s
Age820[7] or 47±8[8] Myr
Other designations
AG+59°378, BD+59°699, HD 22764, HIP 17342, HR 1112, SAO 24169, WDS J03427+5958A[14]
Database references
SIMBADdata

HD 22764, also known as HR 1112, is an orange hued star located in the northern circumpolar constellation Camelopardalis. It has an apparent magnitude of 5.78,[2] allowing it to be faintly visible to the naked eye. The object is located relatively far at a distance of approximately 1,770 light years based on Gaia DR3 parallax measurements[1] but is approaching the Solar System with a heliocentric radial velocity of −12.5 km/s.[4] At its current distance, HD 22764's brightness is diminished by 0.66 magnitudes due to interstellar dust.[5]

The object has two stellar classifications; one states that it is an ageing red giant (K3.5 IIIb)[3] while the other instead lists it as a slightly cooler lower luminosity red supergiant (K4 Ib).[15] The first spectrum hints a close companion to the object of spectral type G. If considered as a supergiant, it has 6.8 times the mass of the Sun;[8] if considered as an older giant star, it has a mass of 2.86 M☉.[7] As a result of its evolved state, HD 22764 has expanded to 167 times the Sun's radius[9] and now radiates 3,342 times the luminosity of the Sun[10] from its photosphere at an effective temperature of 3,928 K.[6] Age estimates range from 47 up to 820 million years.[7][8] It has an iron abundance 65% that of the Sun,[12] making it metal deficient. The object spins leisurely with a projected rotational velocity lower than 1.9 km/s.[13]

HD 22764 is the primary of a binary star[16] consisting of it and HD 22763, a B8 giant star located 54.8" away along a position angle of 38°. There are also 4 line-of-sight companions located near the system.[17]

  1. ^ a b c d e Cite error: The named reference GaiaDR3 was invoked but never defined (see the help page).
  2. ^ a b c d e Cite error: The named reference Ducati2002 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Keenan1989 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Famaey2005 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Mel'nik2017 was invoked but never defined (see the help page).
  6. ^ a b c Cite error: The named reference Messineo2019 was invoked but never defined (see the help page).
  7. ^ a b c d Cite error: The named reference Bertelli1994 was invoked but never defined (see the help page).
  8. ^ a b c d Cite error: The named reference Tetzlaff2011 was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference Kervella2004 was invoked but never defined (see the help page).
  10. ^ a b Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Luck2015 was invoked but never defined (see the help page).
  12. ^ a b Cite error: The named reference Luck2014 was invoked but never defined (see the help page).
  13. ^ a b Cite error: The named reference De Mederios2002 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  15. ^ Cite error: The named reference Appenzeller1967 was invoked but never defined (see the help page).
  16. ^ Cite error: The named reference Eggleton2008 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).