3 Andromedae (HIP 113919)

3 Andromedae is an orange giant star in the constellation Andromeda. It lies about 189 light years away. It is moving through the Galaxy at a speed of 73.3 km/s relative to the Sun.

Sky position: RA 23h 4.2m, Dec +50° 3.1'

Common designations: 3 Andromedae, HR 8780, HD 218031, Gaia DR3 1985791121590368640, HIP 113919

3 Andromedae has the spectral type K0IIIb. K-type stars are orange stars with surface temperatures of about 3,900 to 5,300 K. Their spectra are rich in neutral metal lines and, in the cooler examples, molecular bands. Its luminosity class III marks it as a giant: an evolved star that has left the main sequence and swollen to many times its original size.

How to find 3 Andromedae in the sky

3 Andromedae lies in Andromeda. With a declination of +50° 3.1', it is visible from the entire Northern Hemisphere and from the Southern Hemisphere down to about latitude 40° S. Observers poleward of latitude 40° N see it as circumpolar: it never sets. It is highest in the sky at local midnight around October, which makes the weeks around that month the best time to observe it.

Tabulated data for 3 Andromedae

Astrometry and spectroscopy

Right Ascension (J2000)	346.04576120° (23h 4.2m)
Declination (J2000)	50.05209042° (+50° 3.1')
Galactic Longitude	105.86773497°
Galactic Latitude	-9.23238764°
Proper motion RA	165.84 mas/yr
Proper motion Dec	167.72 mas/yr
Parallax	17.26 ± 0.09 mas
Spectral Type	K0IIIb
Radial Velocity	-34.42 km/s

Photometry

Band	Magnitude	Abs. Mag.
B	5.71	1.90
R	4.00	0.19
J	3.00	-0.82
H	2.46	-1.36
K	2.15	-1.66

Derivations

Heliocentric distance: 57.93 pc (189 light years) (0.5% margin of error)
Transverse velocity: 64.8 km/s
Space velocity relative to the Sun: 73.3 km/s
Galactic position (X, Y, Z): -15.6 pc, 55.0 pc, -9.3 pc
Galactic velocity (U, V, W): -49.8 km/s, -45.5 km/s, 28.8 km/s

Data: Extended Hipparcos Compilation (XHIP) and SIMBAD.