Iota Horologii

Iota Horologii


Credit: Digital Sky Survey/VirGO
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Horologium
Right ascension 02h 42m 33.46667s
Declination −50° 48 01.0551
Apparent magnitude (V) +5.40
Characteristics
Evolutionary stage Main sequence
Spectral type G0Vp
B−V color index 0.57
Astrometry
Radial velocity (Rv)16.94±0.12 km/s
Proper motion (μ) RA: 333.716(35) mas/yr
Dec.: 219.423(42) mas/yr
Parallax (π)57.6131±0.0383 mas
Distance56.61 ± 0.04 ly
(17.36 ± 0.01 pc)
Absolute magnitude (MV)+4.23
Details
Mass1.21±0.01 M
Radius1.16±0.04 R
Luminosity1.64±0.05 L
Surface gravity (log g)4.53±0.03 cgs
Temperature6,207±16 K
Metallicity [Fe/H]+0.180±0.012 dex
Rotation8.19±0.26 days
Rotational velocity (v sin i)6.0±0.5 km/s
Age480±360 Myr
Other designations
ι Hor, GJ 108, HD 17051, HIP 12653, HR 810, 2MASS J02423346-5048008
Database references
SIMBADdata
Exoplanet Archivedata

Iota Horologii, Latinized from ι Horologii, is a star in the Horologium constellation. With an apparent magnitude of +5.40, it can be seen to the naked eye only from places not affected by light pollution. Based on parallax measurements, it lies 56.5 light-years away.

With a spectral type of G0Vp, this is a G-dwarf star, like the Sun, currently fusing hydrogen atoms into helium. It has previously been classified as G3 and a subgiant [IV]. It has 1.21 times the mass of the Sun and 1.16 times the radius. Iota Horologii shines with 1.64 times the Sun's energy output from its photosphere, whose effective temperature is 6,200 K. At this temperature, Iota Horologii has the yellow-white hue typical of early G-type stars. Its age is about one-tenth as that of the Sun, 480 million years, albeit with a large margin of error of 75%.

In 1999, a planet of the star was discovered. Because the planet orbits in a near Earth orbit, Iota Horologii was ranked 69th in the list of candidates for NASA's planned Terrestrial Planet Finder mission. In 2000, a dust disc was announced around the star, but this was later determined to be an instrumental artifact.