108 Aquarii

108 Aquarii

The visual band light curve of 108 Aquarii, showing the variation over the star's 3.7352 day rotation period. Adapted from Adelman (1999)
Observation data
Epoch J2000      Equinox J2000
Constellation Aquarius
Right ascension 23h 51m 21.33832s
Declination −18° 54 32.9937
Apparent magnitude (V) 5.194
Characteristics
Spectral type A0VpSiSr
U−B color index −0.396
B−V color index −0.135
Variable type α² CVn
Astrometry
Radial velocity (Rv)+12.7 km/s
Proper motion (μ) RA: +26.82 mas/yr
Dec.: −4.27 mas/yr
Parallax (π)10.23±0.31 mas
Distance319 ± 10 ly
(98 ± 3 pc)
Absolute magnitude (MV)+0.08
Details
Mass3.21±0.15 M
Radius2.5±0.3 R
Luminosity132 L
Surface gravity (log g)4.27±0.10 cgs
Temperature12,274 K
Metallicity [Fe/H]+0.90 dex
Rotation3.75413 days
Rotational velocity (v sin i)30 km/s
Other designations
BD−19°6522, HD 223640, HIP 117629, HR 9031, SAO 165918
Database references
SIMBADdata

108 Aquarii (abbreviated 108 Aqr) is a star in the equatorial constellation of Aquarius. 108 Aquarii is the Flamsteed designation, although it also bears the Bayer designation i3 Aquarii and the variable star designation ET Aquarii. It has an apparent visual magnitude of 5.194 and can be seen with the naked eye under suitably dark skies. Based upon an annual parallax shift of 10.23 (with a 3% margin of error), the distance to this star is 319 light-years (98 parsecs).

In 1962, Helmut Abt and John C. Golson announced that 108 Aquarii is a variable star. It was given its variable star designation in 1973.

This is an Ap star; meaning it has a peculiar spectrum that shows an overabundance of certain elements. It has more than three times the mass of the Sun and is 2.5 times the Sun's radius. 108 Aquarii is radiating 132 times the luminosity of the Sun from its outer atmosphere at an effective temperature of 12,274 K. At this heat, the star has the white hue of an A-type star.