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 | |
Database references | |
SIMBAD | data |
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]
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]
8 Aquilae 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]