Iota1 Cygni

Iota¹ Cygni is a probable binary star^[7] system in the northern constellation Cygnus. Its name is a Bayer designation that is Latinized from ι¹ Cygni, and abbreviated Iota¹ Cyg or ι¹ Cyg. It is separated by less than a degree from its brighter visual neighbor, Iota² Cygni.^[10] It is near the lower limit of visibility to the naked eye with an apparent visual magnitude of 5.75.^[9] The system is located approximately 387 light years away based on parallax,^[2] and it is drifting further away with a radial velocity of +2 km/s.^[5]

For other stars with this Bayer designation, see ι Cygni.

Iota¹ Cygni

Observation data Epoch J2000      Equinox J2000
Constellation	Cygnus[1]
Right ascension	19h 27m 25.96022s[2]
Declination	+52° 19′ 13.5871″[2]
Apparent magnitude (V)	5.73[1]
Characteristics
Evolutionary stage	main sequence[3]
Spectral type	A1V[4]
B−V color index	−0.002±0.002[1]
Astrometry
Radial velocity (Rv)	+1.90[5] km/s
Proper motion (μ)	RA: −12.639[2] mas/yr Dec.: −27.567[2] mas/yr
Parallax (π)	8.4332±0.0867 mas[2]
Distance	387 ± 4 ly (119 ± 1 pc)
Absolute magnitude (MV)	+0.57[1]
Details
Mass	2.59±0.03[3] M☉
Radius	3.0[6] R☉
Luminosity	74.1+11.0 −20.5[7] L☉
Surface gravity (log g)	4.18[7] cgs
Temperature	9,683+89 −178[3] K
Metallicity [Fe/H]	0.00[8] dex
Rotational velocity (v sin i)	51.6±2.2[7] km/s
Age	386[8] Myr
Other designations
ι1 Cyg, 7 Cygni, BD+52°2434, HD 183534, HIP 95656, HR 7408, SAO 31673[9]
Database references
SIMBAD	data

This is a candidate double-lined spectroscopic binary system.^[7] It has a stellar classification of A1V,^[4] suggesting the primary component is an A-type main-sequence star. The star is about 400 million years old^[8] with a moderate rotation rate, showing a projected rotational velocity of 52 km/s.^[7] It has 2.6 times the mass of the Sun^[3] and is radiating 74 times the Sun's luminosity^[7] from its photosphere at an effective temperature of 9,683 K.^[3]