HD 11928

HD 11928
Location of HD 11928 on the map (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Triangulum
Right ascension 01h 57m 43.74417s[1]
Declination +27° 48′ 15.7579″[1]
Apparent magnitude (V) 5.84 - 5.85[2]
Characteristics
Evolutionary stage AGB[3]
Spectral type M2 III[4]
B−V color index +1.60[5]
Variable type suspected[2]
Astrometry
Radial velocity (Rv)−1.93±0.22[6] km/s
Proper motion (μ) RA: +12.974 mas/yr[1]
Dec.: −60.043 mas/yr[1]
Parallax (π)6.1432 ± 0.1953 mas[1]
Distance530 ± 20 ly
(163 ± 5 pc)
Absolute magnitude (MV)+0.11[7]
Details
Radius52.68[8] R☉
Luminosity485±17[9] L☉
Surface gravity (log g)1.024[10] cgs
Temperature3,656±72[11] K
Other designations
NSV 15408, AG+27°211, BD+27°310, GC 2357, HD 11928, HIP 9132, HR 564, SAO 75048[12]
Database references
SIMBADdata

HD 11928 (HR 564; NSV 15408) is a solitary star[13] located in the northern constellation of Triangulum. It is faintly visible to the naked eye as a red-hued point of light with an apparent magnitude of 5.85.[14] Gaia DR3 parallax measurements imply a distance of 530 light-years and it is drifting closer with a heliocentric radial velocity of −1.93 km/s.[6] At its current distance, HD 11928's brightness is diminished by an interstellar extinction of 0.13 magnitudes[15] and it has an absolute magnitude of +0.11.[7]

HD 11928 has a stellar classification of M2 III,[4] indicating that is an evolved M-type giant star. It is currently an asymptotic giant branch star that is generating energy via the fusion of hydrogen and helium shells around an inert carbon core. At present it has expanded to 52.68 times the radius of the Sun[8] and it radiates 485 times the luminosity of the Sun[9] from its photosphere at an effective temperature of 3,656 K.[11]

In 1997, the Hipparcos satellite observed that the star varied from 5.89 to 5.93 in the Hipparcos passband.[16] Further observations from Koen & Eyer reveal that HD 11928 flucates between 5.84 and 5.85 in the visual passband within 50.7 days.[17] As of 2004 however, its variability has not been confirmed,[18] but it is still suspected to be variable.

  1. ^ a b c d Cite error: The named reference GaiaDR3 was invoked but never defined (see the help page).
  2. ^ a b Cite error: The named reference Samus2017 was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference Eggen1992 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Wilson1950 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference Haggkvist1970 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Famaey2005 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference Stassun2019 was invoked but never defined (see the help page).
  9. ^ a b Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference McDonald2017 was invoked but never defined (see the help page).
  11. ^ a b Cite error: The named reference van Belle1999 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 Eggleton2008 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference Tycho2000 was invoked but never defined (see the help page).
  15. ^ Cite error: The named reference Gontcharov2017 was invoked but never defined (see the help page).
  16. ^ Cite error: The named reference Perryman1997 was invoked but never defined (see the help page).
  17. ^ Cite error: The named reference Koen2002 was invoked but never defined (see the help page).
  18. ^ Cite error: The named reference Samus2004 was invoked but never defined (see the help page).