Lambda Horologii

Lambda Horologii
Observation data
Epoch J2000      Equinox J2000
Constellation Horologium
Right ascension 02h 24m 53.91034s[1]
Declination −60° 18′ 43.0170″[1]
Apparent magnitude (V) +5.35[2]
Characteristics
Spectral type F2III[3]
B−V color index +0.39[2]
Astrometry
Radial velocity (Rv)+28.34±0.41[1] km/s
Proper motion (μ) RA: −71.892[1] mas/yr
Dec.: −131.088[1] mas/yr
Parallax (π)21.0119 ± 0.1004 mas[1]
Distance155.2 ± 0.7 ly
(47.6 ± 0.2 pc)
Absolute magnitude (MV)+1.91[4]
Details
Mass1.76[5] M☉
Radius2.74+0.11
−0.16[1] R☉
Luminosity13.3±0.1[1] L☉
Surface gravity (log g)3.66[6] cgs
Temperature6,848[5] K
Metallicity [Fe/H]−0.12[5] dex
Rotational velocity (v sin i)+140[3] km/s
Age1.4[5] Gyr
Other designations
λ Hor, CPD−60° 199, FK5 84, HD 15233, HIP 11258, HR 714, SAO 248555[7]
Database references
SIMBADdata

λ Horologii, Latinised as Lambda Horologii, is a star in the southern constellation of Horologium. It is a yellow-white hued star that is dimly visible to the naked eye with an apparent visual magnitude of +5.35.[2] Based upon parallax, this object is located 155 light years distance from the Sun. It is drifting further away with a radial velocity of +28 km/s.[1] Although Eggleton and Tokovinin (2008) list this as a single star,[8] according to Kunzli and North (1998) it may be a binary system with a long orbital period.[9]

The visible component has a stellar classification of F2III,[3] matching an evolved star that has, at the age of 1.4 billion years,[5] become a giant. However, it has just 2.74[1] times the Sun's radius and shows a high rate of spin with a projected rotational velocity of +140 km/s.[3] The star has 1.76[5] times the mass of the Sun and is radiating 13[1] times the Sun's luminosity from its photosphere at an effective temperature of 6,848 K.[5]

  1. ^ a b c d e f g h i j k Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  2. ^ a b c Cite error: The named reference Johnson1966 was invoked but never defined (see the help page).
  3. ^ a b c d Cite error: The named reference belle was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference vonEiff2012 was invoked but never defined (see the help page).
  5. ^ a b c d e f g Cite error: The named reference aa530_A138 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference David2015 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Kunzli1998 was invoked but never defined (see the help page).