Delta Andromedae

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**δ Andromedae A / B / C**
Observation data Epoch J2000
Image:NSV 15142.jpg Delta Andromedae (NGC 1442 or GC 774)
Constellation (pronunciation)	Andromeda
Right ascension	00h 39m 19.6758s
Declination	+30° 51' 39.686"'
Apparent magnitude (V)	3.28
Characteristics
Spectral type	K3III
U-B color index	1.48
B-V color index	1.28
Variable type	None
Astrometry
Radial velocity (R_v)	-7.3 km/s
Proper motion (μ)	RA: 115.38 mas/yr Dec.: -83.05 mas/yr
Parallax (π)	32.19 ± 0.68 mas
Distance	101 ± 2 ly (31.1 ± 0.7 pc)
Absolute magnitude (M_V)	4.56
Details
Mass	0.8 M_☉
Radius	0.9 R_☉
Surface gravity (log g)	?
Luminosity	0.4 L_☉
Temperature	4000 K
Metallicity	?
Rotation	?
Age	? years
Visual binary orbit
Companion	δ Andromedae B
Semimajor axis (a)	28.7"
Eccentricity (e)	0.0
Inclination (i)	298°
Visual binary orbit
Companion	δ Andromedae C
Period (P)	41.0 yr
Semimajor axis (a)	41.4"
Eccentricity (e)	0.0
Inclination (i)	108°
Other designations
NSV 15142, GCRV 357, JP11 399, 31 And, GSC 02275-01753, 2MASS J00391967+3051397, TD1 355, ADS 548 A, HD 3627, N30 129, TYC 2275-1753-1, AG+30° 64, HIC 3092, PLX 108, UBV 506, ASCC 550189, HIP 3092, PMC 90-93 14, UBV M 7538, BD+30° 91, HR 165, PPM 65514, USNO 790, CCDM J00393+3052A, IDS 00340+3019 A, RAFGL 94, YZ 30° 378, CSI+30 91 1, IRAS F00366+3035, ROT 120, FK5 20, IRAS 00366+3035, SAO 54058, GC 774, IRC +30014, SBC7 23.
Database references
SIMBAD	data

Delta Andromedae (δ And / δ Andromedae) is a triple star system in the constellation Andromeda. It is approximately 101 light years from Earth. It has a proper name variously spelled Sadiradra, Saderazra, Sadir Elazra, from its Arabic name الصدر العذراء al-sadr al-adhra'a "Bosom of the Maiden".

The primary component, δ Andromedae A, is an orange K-type giant with an apparent magnitude of +3.27. It is a long period spectroscopic binary with an orbital period of approximately 15 000 days (41 years). It has a companion, the 13th magnitude δ Andromedae B, which is 28.7 arcseconds distant.