HD 187420/187421

HD 187420/187421
Location of HD 187420 and 187421 (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Telescopium
HD 187420
Right ascension 19h 52m 37.72117s[1]
Declination −54° 58′ 15.6700″[1]
Apparent magnitude (V) 5.71±0.01[2]
HD 187421
Right ascension 19h 52m 39.13201s[3]
Declination −54° 58′ 35.1997″[3]
Apparent magnitude (V) 6.37±0.01[2]
Characteristics
HD 187420
Spectral type G8/K0 III[4]
U−B color index +0.67[5]
B−V color index +0.92[5]
HD 187421
Spectral type A1/3 V[4]
U−B color index +0.13[5]
B−V color index +0.10[5]
Astrometry
HD 187420
Radial velocity (Rv)−17.9±1.2[6] km/s
Proper motion (μ) RA: +18.630 mas/yr[1]
Dec.: +3.076 mas/yr[1]
Parallax (π)8.0046 ± 0.0705 mas[1]
Distance407 ± 4 ly
(125 ± 1 pc)
Absolute magnitude (MV)−0.33[7]
HD 187421
Radial velocity (Rv)−21.5±1.9[8] km/s
Proper motion (μ) RA: +19.549 mas/yr[3]
Dec.: +2.252 mas/yr[3]
Parallax (π)7.8714 ± 0.037 mas[3]
Distance414 ± 2 ly
(127.0 ± 0.6 pc)
Absolute magnitude (MV)+2.69[7]
Details
HD 187420
Mass3.00±0.04[1] M☉
Radius11.6±0.6[9] R☉
Luminosity88.3+1.4
−1.5[1] L☉
Surface gravity (log g)2.59[10] cgs
Temperature5,140±122[11] K
Metallicity [Fe/H]−0.17[12] dex
Rotational velocity (v sin i)2.4±1.2[13] km/s
Age377±37[1] Myr
HD 187421
Mass2.31[14] M☉
Radius2.72±0.14[9] R☉
Luminosity37.1+2.4
−2.0[11] L☉
Surface gravity (log g)3.92[14] cgs
Temperature9,099±309[14] K
Metallicity [Fe/H]+0.20[15] dex
Rotational velocity (v sin i)170±2[16] km/s
Age560[14] Myr
Other designations
HD 187420: 71 G. Telescopii[17], CD−55°8312, CPD−55°9221, GC 27482, HD 187420, HIP 97816, HR 7548, SAO 246311, CCDM J19526-5458A, WDS J19526-5458A[18]
HD 187421: 72 G. Telescopii[17], CD−55°8313, CPD−55°9222, GC 27483, HD 187421, HIP 97819, HR 7549, SAO 246312, CCDM J19526-5458B, WDS J19526-5458B[19]
Database references
SIMBADHD 187420
HD 187421

HD 187420 (HR 7548; 71 G. Telescopii) and HD 187421 (HR 7549; 72 G. Telescopii), are the components of a binary star located in the southern constellation Telescopium. Gaia DR3 parallax measurements place the stars at a distance of 407 and 414 light years respectively.[1][3] The two are separated by 23″, and they are approaching the Solar System with heliocentric radial velocities of −17.9 km/s and −21.5 km/s respectively.[6][8]

  1. ^ a b c d e f g h Cite error: The named reference GaiaDR3A 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 Cite error: The named reference GaiaDR3B was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Houk1975 was invoked but never defined (see the help page).
  5. ^ a b c d Cite error: The named reference Wayman1962 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Gontcharov2006 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 Kharchenko2007 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. ^ Cite error: The named reference Perdigon2021 was invoked but never defined (see the help page).
  11. ^ a b Cite error: The named reference Stassun2019 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Anders2019 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference De Medeiros2014 was invoked but never defined (see the help page).
  14. ^ a b c d Cite error: The named reference David2015 was invoked but never defined (see the help page).
  15. ^ Cite error: The named reference Anders2022 was invoked but never defined (see the help page).
  16. ^ Cite error: The named reference Díaz2011 was invoked but never defined (see the help page).
  17. ^ a b Cite error: The named reference Gould1879 was invoked but never defined (see the help page).
  18. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  19. ^ Cite error: The named reference SIMBAD2 was invoked but never defined (see the help page).