8 Aquilae

8 Aquilae is a star in the equatorial constellation of Aquila,^[10] located 271 light years away from the Sun. 8 Aquilae is the Flamsteed designation. It can be viewed with the naked eye in good seeing conditions, appearing as a dim, yellow-white hued star with an apparent visual magnitude of 6.08.^[3] The star is moving further from the Earth with a heliocentric radial velocity of +12 km/s.^[3]

8 Aquilae

A blue band light curve for 8 Aquilae, adapted from Machado et al. (2007)[1]
Observation data Epoch J2000      Equinox J2000
Constellation	Aquila
Right ascension	18h 51m 22.15821s[2]
Declination	−03° 19′ 04.2851″[2]
Apparent magnitude (V)	6.08[3]
Characteristics
Spectral type	F0 IV[4] or F2 III[5]
U−B color index	+0.06[6]
B−V color index	+0.299±0.007[7]
Variable type	δ Sct[5]
Astrometry
Radial velocity (Rv)	+11.8[3] km/s
Proper motion (μ)	RA: +2.019[2] mas/yr Dec.: −21.411[2] mas/yr
Parallax (π)	12.0549±0.0268 mas
Distance	270.6 ± 0.6 ly (83.0 ± 0.2 pc)
Absolute magnitude (MV)	1.27[5]
Details
Mass	1.60[8] M☉
Radius	3.0[2] R☉
Luminosity	18.89[7] L☉
Surface gravity (log g)	3.88±0.14[8] cgs
Temperature	7,395±251[8] K
Metallicity [Fe/H]	0.14[5] dex
Rotational velocity (v sin i)	105[9] km/s
Age	959[8] Myr
Other designations
8 Aql, V1729 Aql, BD−03°4392, FK5 3500, HD 174589, HIP 92524, HR 7101, SAO 142706[10]
Database references
SIMBAD	data

Abt and Morrell (1995) found a stellar classification of F0 IV^[4] for this star, suggesting it is an F-type subgiant. In their 2010 study, Fox Machado et al. assigned a class of F2 III,^[5] which matches an evolved giant star. Despite the spectral classifications, evolutionary models place the star towards the end of its main sequence life, with an age of about a billion years.^[8][2]

Lester Fox Machado et al. discovered that 8 Aquilae is a variable star during observations conducted in 2003, and published in 2007.^[1] It is a Delta Scuti variable with at least three overlapping pulsation frequencies, although the total amplitude of its brightness variations is only about 0.02 magnitudes.^[5] It has a relatively high rotation rate, showing a projected rotational velocity of 105 km/s.^[9] It has 1.6^[8] times the mass of the Sun and is radiating 19^[7] times the Sun's luminosity from its photosphere at an effective temperature of about 7,395 K.^[8]