Iota Eridani

ι Eridani
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Eridanus
Right ascension 02h 40m 40.03501s[1]
Declination −39° 51′ 19.3541″[1]
Apparent magnitude (V) 4.11[2]
Characteristics
Evolutionary stage Red clump[3]
Spectral type K0 III[4]
U−B color index +0.74[2]
B−V color index +1.02[2]
Astrometry
Radial velocity (Rv)−9.30±0.70[5] km/s
Proper motion (μ) RA: +135.92[1] mas/yr
Dec.: −27.53[1] mas/yr
Parallax (π)21.65 ± 0.18 mas[1]
Distance151 ± 1 ly
(46.2 ± 0.4 pc)
Absolute magnitude (MV)0.877[3]
Details[6]
Mass1.29±0.01 M☉
Radius11.17±0.06 R☉
Luminosity54.7±0.5 L☉
Surface gravity (log g)2.65±0.10 cgs
Temperature4,700±30 K
Metallicity [Fe/H]−0.34±0.02 dex
Age3.55±0.12 Gyr
Other designations
ι Eri, CD−40° 689, FK5 1075, HD 16815, HIP 12486, HR 794, SAO 215999.[7]
Database references
SIMBADdata

Iota Eridani (ι Eri) is a solitary star in the constellation Eridanus. It is visible to the naked eye with an apparent magnitude of 4.11.[2] With an annual parallax shift of 0.02165 arcseconds,[1] it lies at an estimated distance of about 151 light years.

This is an evolved giant star with a stellar classification of K0 III.[4] The measured angular diameter, after correcting for limb darkening, is 2.248±0.014 mas. This star is 3.55 billion years old, sufficient to have exhausted the hydrogen at its core and reached a red clump stage. It is only around 29% more massive than the Sun, but is eleven times larger. It radiates 54.7 times the solar luminosity from its outer atmosphere at an effective temperature of 4,700 K.[6]

  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 Johnson1996 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Liu2007 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference houk1978 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference deBruijne2012 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Gallenne2017 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).