HD 138867

HD 138867
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Apus
Right ascension 15h 41m 54.68806s[1]
Declination −76° 04′ 55.0718″[1]
Apparent magnitude (V) 5.94±0.01[2]
Characteristics
Evolutionary stage main sequence[3]
Spectral type B9.5 V[4]
Astrometry
Radial velocity (Rv)1.1±1.7[5] km/s
Proper motion (μ) RA: −12.407 mas/yr[1]
Dec.: −41.541 mas/yr[1]
Parallax (π)7.8146 ± 0.0916 mas[1]
Distance417 ± 5 ly
(128 ± 1 pc)
Absolute magnitude (MV)+0.4[6]
Details
Mass2.81[3] M☉
Radius2.59±0.09[7] R☉
Luminosity54.9[8] L☉
Surface gravity (log g)4.04±0.07[7] cgs
Temperature10,375±48[3] K
Metallicity [Fe/H]0.00[9] dex
Rotational velocity (v sin i)178[10] km/s
Age272[9] Myr
Other designations
34 G. Apodis[11], CPD−75°1222, FK5 3235, GC 21025, HD 138867, HIP 76877, HR 5786, SAO 257310[12]
Database references
SIMBADdata

HD 138867, also known as HR 5786, is a bluish-white hued star located in the southern circumpolar constellation Apus. It has an apparent magnitude of 5.94,[2] making it faintly visible to the naked eye if viewed under ideal conditions. Based on parallax measurements from the Gaia spacecraft, it is estimated to be 417 light years away from Earth.[1] However, it is receding with a heliocentric radial velocity of 1.1 km/s.[5]

HD 138867 has a stellar classification of B9.5 V,[4] indicating that it is a B-type main-sequence star just shy of being an A-type star. It has 2.81 times the mass of the Sun[3] and is estimated to be 272 million years,[9] having completed 67.4% of its main sequence lifetime.[3] HD 138867 has an effective temperature of 10,375 K,[3] which combined with a radius of 2.59 R☉,[7] yields a luminosity over 50 times that of Sun.[8] A solar metallicity has been calculated for HD 138867.[9] It is currently spinning rapidly with a projected rotational velocity of 178 km/s.[10]

There has been disagreement in regards to HD 138867's muplicity. Chini et al. (2012) list it as a solitary star[13] while Eggleton and Tokovinn (2008) found it to be an astrometric binary.[14] The first one is more likely as the object has a constant radial velocity.

  1. ^ a b c d e 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 e f Cite error: The named reference Zorec2012 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Abt1995 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Gontcharov2006 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  7. ^ a b c Cite error: The named reference Stassun2019 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference McDonald2017 was invoked but never defined (see the help page).
  9. ^ a b c d Cite error: The named reference Gontcharov2012 was invoked but never defined (see the help page).
  10. ^ a b Cite error: The named reference Levato2004 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Gould1879 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference Chini2012 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).