Delta Horologii

Delta Horologii
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Horologium
Right ascension 04h 10m 50.58927s[1]
Declination −41° 59′ 36.8537″[1]
Apparent magnitude (V) 4.93[2] (5.15 + 7.29)[3]
Characteristics
Spectral type A9 V[3]
U−B color index +0.084[2]
B−V color index +0.338[2]
Astrometry
Radial velocity (Rv)+38.3±2.6[4] km/s
Proper motion (μ) RA: +199.08[1] mas/yr
Dec.: +70.18[1] mas/yr
Parallax (π)18.24 ± 0.41 mas[1]
Distance179 ± 4 ly
(55 ± 1 pc)
Absolute magnitude (MV)1.50[5]
Details
δ Hor A
Mass1.41[6] M☉
Surface gravity (log g)3.71±0.14[6] cgs
Temperature7,033±239[6] K
Metallicity [Fe/H]−0.32[7] dex
Rotational velocity (v sin i)220.1±11.0[5] km/s
Age768[6] Myr
δ Hor B
Rotational velocity (v sin i)51.7±2.6[5] km/s
Other designations
δ Hor, CD−42° 1400, HD 26612, HIP 19515, HR 1302, SAO 216682, WDS J04108-4200AB[8]
Database references
SIMBADdata

Delta Horologii (δ Horologii) is a binary star[3] system in the constellation Horologium. It is visible to the naked eye with a combined apparent visual magnitude of 4.93.[2] As of 2014, the pair had an angular separation of 0.20 arc seconds along a position angle of 24°.[9] Based upon an annual parallax shift of 18.24 mas as seen from Earth,[1] it is located 179 ± 4 light years from the Sun.

The primary, component A, is a magnitude 5.15 A-type main sequence star with a stellar classification of A9 V.[3] At the estimated age of 768 million years,[6] it is spinning rapidly with a projected rotational velocity of 220 km/s,[5] giving the star an oblate shape with an equatorial bulge that is 15% larger than the polar radius.[10] The star has 1.4[6] times the mass of the Sun.

The secondary has an apparent magnitude of 7.29.[3]

  1. ^ a b c d e f Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference Cousins1983 was invoked but never defined (see the help page).
  3. ^ a b c d e Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference deBruijne2012 was invoked but never defined (see the help page).
  5. ^ a b c d Cite error: The named reference AmmlerVonEiff2012 was invoked but never defined (see the help page).
  6. ^ a b c d e f Cite error: The named reference David2015 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference Casagrande2011 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference WDSC2014 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference belle2012 was invoked but never defined (see the help page).