HD 130458

HD 130458
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Apus
A
Right ascension 14h 53m 13.6598s[1]
Declination −73° 11′ 23.837″[1]
Apparent magnitude (V) 5.77±0.01[2]
B
Right ascension 14h 53m 14.0752s[3]
Declination −73° 11′ 25.2484″[3]
Apparent magnitude (V) 7.54±0.01[2]
Characteristics
A
Evolutionary stage Horizontal branch[4]
Spectral type G7 IIIa[5] (G8 IIb)[4]
U−B color index +0.42[6]
B−V color index +0.82[6]
B
Spectral type F9 IV[5]
Astrometry
Radial velocity (Rv)+31.4 ± 2.5[7] km/s
Absolute magnitude (MV)+0.58[8]
A
Proper motion (μ) RA: +15.901[1] mas/yr
Dec.: +28.871[1] mas/yr
Parallax (π)10.5077 ± 0.3522 mas[1]
Distance310 ± 10 ly
(95 ± 3 pc)
B
Proper motion (μ) RA: +20.669[3] mas/yr
Dec.: +19.875[3] mas/yr
Parallax (π)10.0654 ± 0.0476 mas[3]
Distance324 ± 2 ly
(99.4 ± 0.5 pc)
Details
A
Mass1.5[9] M☉
Radius8.87[10] R☉
Luminosity54.7[11] L☉
Surface gravity (log g)2.65[9] cgs
Temperature5194±124[10] K
Metallicity [Fe/H]−0.17[9] dex
Rotational velocity (v sin i)3.6±1[12] km/s
B
Mass1.41[9] M☉
Radius2.8[13] R☉
Luminosity7.5[14] L☉
Surface gravity (log g)3.96[9] cgs
Temperature6,601[9] K
Metallicity [Fe/H]−0.18[9] dex
Other designations
17 G. Apodis[15], CPD−72°1604, GC 19976, HD 130458, HIP 72833, HR 5520, SAO 257206, WDS J14532-7311AB[16]
Database references
SIMBADdata

HD 130458 (HR 5520) is a double star[17] in the southern circumpolar constellation of Apus. The pair has a combined apparent magnitude of 5.8,[6] making it faintly visible to the naked eye under ideal conditions. Parallax measurements place the system 310-24 light years away[1] and it is receding with a heliocentric radial velocity of 31.4 km/s.[7]

The primary is a red giant with a stellar classification of G7 IIIa. It was earlier classified as G8 IIb, indicating a bright giant.The dimmer component has a stellar classification of F9 IV, indicating that it is an F-type subgiant evolving onto the red giant branch. As of 2008 , the pair has an angular separation of 2.167″.[17]

At present the primary has 1.5 times the mass of the Sun[9] but has expanded to 8.9[10] times its girth. It radiates at 55[11] times the luminosity of the Sun from its enlarged photosphere at an effective temperature 5,194 K,[10] which gives it a yellow glow. Currently it spins leisurely with a projected rotational velocity of 3.6 km/s,[12] common for giants. HD 130458A is believed to be on the horizontal branch.[4]

As for the secondary component, it has 1.4 times the mass of the Sun and an effective temperature of 6,601 K, giving a yellowish white hue. [9]

  1. ^ a b c d e f Cite error: The named reference EDR3 was invoked but never defined (see the help page).
  2. ^ a b Cite error: The named reference Fabricius2002 was invoked but never defined (see the help page).
  3. ^ a b c d e Cite error: The named reference EDR3B was invoked but never defined (see the help page).
  4. ^ a b c Cite error: The named reference Corbally1980 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Corbally1984 was invoked but never defined (see the help page).
  6. ^ a b c Cite error: The named reference clpl4_99 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. ^ Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  9. ^ a b c d e f g h i Cite error: The named reference Anders2019 was invoked but never defined (see the help page).
  10. ^ a b c d Cite error: The named reference Stassun2019 was invoked but never defined (see the help page).
  11. ^ a b Cite error: The named reference McDonald2012 was invoked but never defined (see the help page).
  12. ^ a b Cite error: The named reference DeMed2002 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference montalto2021 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference DR2B was invoked but never defined (see the help page).
  15. ^ Cite error: The named reference Gould1879 was invoked but never defined (see the help page).
  16. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  17. ^ a b Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).