HD 192827

HD 192827
Location of HD 192827 and HD 192886 (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Telescopium
Right ascension 20h 18m 55.97916s[1]
Declination −47° 42′ 38.8042″[1]
Apparent magnitude (V) 6.28±0.01[2]
Characteristics
Evolutionary stage AGB[3]
Spectral type M1 III[4]
B−V color index +1.47[5]
Variable type suspected[6]
Astrometry
Radial velocity (Rv)−43.7±0.9[7] km/s
Proper motion (μ) RA: +14.547 mas/yr[1]
Dec.: −3.934 mas/yr[1]
Parallax (π)2.4785 ± 0.0638 mas[1]
Distance1,320 ± 30 ly
(400 ± 10 pc)
Absolute magnitude (MV)−1.07[8]
Details
Mass1.21[9] M☉
Radius119±6[10] R☉
Luminosity1242±71[11] L☉
Surface gravity (log g)0.57[9] cgs
Temperature3,786±122[12] K
Metallicity [Fe/H]−0.24[9] dex
Other designations
83 G. Telescopii[13], NSV 25083, CD−48°13509, CPD−48°10371, FK5 1528, GC 28202, HD 192827, HIP 100151, HR 7745, SAO 230144[14]
Database references
SIMBADdata

HD 192827, also known as HR 7745 or rarely 83 G. Telescopii, is a solitary red hued star located in the southern constellation Telescopium. It has an apparent magnitude of 6.28,[2] placing it near the limit for naked eye visibility. The object is located relatively far at a distance of 1,320 light years based on Gaia DR3 parallax measurements,[1] but it is approaching with a heliocentric radial velocity of −43.7 km/s.[7] At its current distance, HD 192827's brightness is diminished by 0.19 magnitudes due to interstellar dust[15] and it has an absolute magnitude of −1.07.[8]

A light curve for HD 192827, plotted from Hipparcos data[16]

HD 192827 has a stellar classification of M1 III,[4] indicating that it is an evolved red giant. It is currently on the asymptotic giant branch,[3] generating energy by fusing hydrogen and helium shells around an inert carbon core. Having exhausted hydrogen at its core, HD 192827 has expanded to 119 times the radius of the Sun[10] and now radiates 1,242 times the luminosity of the Sun[11] from its enlarged photosphere at an effective temperature of 3,786 K.[12] It has a comparable mass to the Sun[9] and has a metallicity of [Fe/H] = −0.24, making it metal deficient.[9]

HD 192827 was first suspected to be variable in 1997 by the Hipparcos satellite.[17] It fluctuates between magnitudes 6.34 and 6.40 in the Hipparcos passband.[6] As of 2004 however, HD 192827 has not been confirmed to be variable.[18]

  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 Cite error: The named reference Eggen1992 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Houk1978 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference Stoy1968 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Samus2017 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference Gontcharov2006 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  9. ^ a b c d e Cite error: The named reference Anders2019 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. ^ a b Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  12. ^ a b Cite error: The named reference Stassun2019 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference Gould1879 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 Gontcharov2017 was invoked but never defined (see the help page).
  16. ^ Cite error: The named reference CDS was invoked but never defined (see the help page).
  17. ^ Cite error: The named reference Perryman1997 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).