Iota Phoenicis

ι Phoenicis, Latinized as Iota Phoenicis, is a binary star^[9] system in the southern constellation of Phoenix, near the constellation border with Grus. It is visible to the naked eye as a faint, white-hued star with an apparent visual magnitude that fluctuates around 4.71.^[2] This system lies approximately 254 light years from the Sun based on parallax, and it is drifting further away with a radial velocity of +19.4 km/s.^[4]

A light curve for Iota Phoenicis, plotted from TESS data,^[10]

Iota Phoenicis

Location of ι Phoenicis (circled)
Observation data Epoch J2000      Equinox J2000
Constellation	Phoenix
Right ascension	23h 35m 04.57082s[1]
Declination	−42° 36′ 54.5409″[1]
Apparent magnitude (V)	4.71[2] (4.70 - 4.75)[3]
Characteristics
Evolutionary stage	main sequence[3]
Spectral type	A2VpSrCrEu[3]
U−B color index	+0.07[2]
B−V color index	+0.08[2]
Variable type	α2 CVn[3]
Astrometry
Radial velocity (Rv)	+19.4[4] km/s
Proper motion (μ)	RA: +39.908[1] mas/yr Dec.: + 10.844[1] mas/yr
Parallax (π)	12.8425±0.3922 mas[1]
Distance	254 ± 8 ly (78 ± 2 pc)
Absolute magnitude (MV)	0.28[5]
Details
Mass	2.23[6] M☉
Radius	5.07+0.51 −0.42[1] R☉
Luminosity	68.2±3.3[1] L☉
Surface gravity (log g)	3.89[6] cgs
Temperature	7,370+320 −350[1] K
Metallicity [Fe/H]	-0.01[7] dex
Rotational velocity (v sin i)	23[6] km/s
Age	573[6] Myr
Other designations
ι Phe, CD−43°15420, FK5 1617, HD 221760, HIP 116389, HR 8949, SAO 231675, CCDM J23351-4237A, WDS J23351-4237A[8]
Database references
SIMBAD	data

The primary component is an Ap star on the main sequence with a stellar classification of A2VpSrCrEu,^[3] where the suffix notation indicates abnormal abundances of strontium, chromium, and europium in the stellar atmosphere. It is an Alpha² Canum Venaticorum variable; its apparent magnitude varies from 4.70 down to 4.75 with a period of 12.5 days.^[3] A rotationally-modulated magnetic field has been measured, varying from −72±9 G to 57±9 G. It has an estimated rotation period of 5.98±0.06 d, although this is in need of further confirmation.^[11]

The proper motion companion^[12] is a magnitude 12.8 star at an angular separation of 6.7″.^[9]