14 Aquarii

14 Aquarii (abbreviated 14 Aqr) is red giant star. 14 Aquarii is the Flamsteed designation; it also bears the variable star designation IW Aquarii. It is a semiregular variable with an amplitude of a tenth of a magnitude, and shows variations on a timescale of just one day.^[4] At its brightest, magnitude 6.44,^[7] it could be faintly visible to the naked eye under ideal observing conditions.

14 Aquarii

A light curve for IW Aquarii, plotted from Hipparcos data[1]
Observation data Epoch J2000      Equinox J2000
Constellation	Aquarius
Right ascension	21h 16m 17.7734s[2]
Declination	−09° 12′ 52.795″[2]
Apparent magnitude (V)	6.44 - 6.55[3]
Characteristics
Evolutionary stage	red giant branch[2]
Spectral type	M4III:[4]
B−V color index	1.57[5]
Variable type	Semiregular[4]
Astrometry
Radial velocity (Rv)	8.00[6] km/s
Proper motion (μ)	RA: −1.597[2] mas/yr Dec.: +3.549[2] mas/yr
Parallax (π)	2.4622±0.0685 mas[2]
Distance	1,320 ± 40 ly (410 ± 10 pc)
Absolute magnitude (MV)	−2.3[4]
Details[2]
Mass	1.9 M☉
Radius	106 R☉
Luminosity	2,145 L☉
Surface gravity (log g)	+0.36 cgs
Temperature	3,542 K
Metallicity [Fe/H]	−0.4 dex
Age	1.5 Gyr
Other designations
IW Aquariii, BD−09°5700, HD 202466, HIP 105019, SAO 145251.
Database references
SIMBAD	data

In 1996 the variability of the brightness of 14 Aquarii was first detected, in the Hipparcos satellite data, resulting in the publication of its variable star designation in 1999.^[8]