Eta Scuti

Eta Scuti, Latinized from η Scuti, is a single^[10] star in the southern constellation of Scutum, near the constellation border with Aquila. Eta Scuti was a latter designation of 9 Aquilae before the official constellation borders were set in 1922.^[11] It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of +4.83.^[1] This object is located approximately 213 light-years from the Sun based on parallax, and is moving closer with a radial velocity of −92 km/s.^[2]

η Scuti

Location of η Scuti (circled)
Observation data Epoch J2000      Equinox J2000
Constellation	Scutum[1]
Right ascension	18h 57m 03.67027s[2]
Declination	−05° 50′ 46.7305″[2]
Apparent magnitude (V)	4.83[1]
Characteristics
Evolutionary stage	horizontal branch[3]
Spectral type	K1-III[4]
U−B color index	+1.02[5]
B−V color index	+1.08[5]
Astrometry
Radial velocity (Rv)	−92.22±0.16[2] km/s
Proper motion (μ)	RA: +61.545[2] mas/yr Dec.: −41.429[2] mas/yr
Parallax (π)	15.2960±0.1740 mas[2]
Distance	213 ± 2 ly (65.4 ± 0.7 pc)
Absolute magnitude (MV)	0.87[1]
Details
Mass	1.50[6] M☉
Radius	11.97+0.18 −0.13[2] R☉
Luminosity	62.7±0.8[2] L☉
Surface gravity (log g)	2.54[6] cgs
Temperature	4,693+27 −266[2] K
Metallicity [Fe/H]	−0.03[6] dex
Rotational velocity (v sin i)	< 1.0[7] km/s
Age	2.8[8] Gyr
Other designations
η Sct, BD−06°4976, FK5 3821, GC 26013, HD 175751, HIP 93026, HR 7149, SAO 142838, GSC 05127-07358[9]
Database references
SIMBAD	data

This is an aging giant star with a stellar classification of K1-III.^[4] After exhausting the supply of hydrogen at its core, the star cooled and expanded until currently it has 12^[2] times the girth of the Sun. It is a red clump giant, which indicates it is presently on the horizontal branch and is generating energy through core helium fusion.^[3] The star is about 2.8 billion years old^[8] with 1.5 times the mass of the Sun.^[6] It is radiating 63^[2] times the Sun's luminosity from its swollen photosphere at an effective temperature of 4,693 K.^[2]