Sigma Aquilae

**σ Aquilae**
Observation data Epoch J2000
Image:Sigma Aquilae.jpg σ Aquilae
Constellation (pronunciation)	Aquila
Right ascension	19^h 39^m 11.6415^s
Declination	+05° 23′ 51.984″
Apparent magnitude (V)	5.178
Characteristics
Spectral type	B3V+
U-B color index	-0.6
B-V color index	0.03
Variable type	Beta Lyrae variables
Astrometry
Radial velocity (R_v)	-4.8 km/s
Proper motion (μ)	RA: 2.08 mas/yr Dec.: -3.78 mas/yr
Parallax (π)	4.78 ± 0.82 mas
Distance	approx. 700 ly (approx. 210 pc)
Absolute magnitude (M_V)	5.176
Details
Mass	? M_☉
Radius	? R_☉
Luminosity	? L_☉
Temperature	? K
Metallicity	?
Rotation	0.00533952 Year
Age	? years
Visual binary orbit
Companion	σ Aquilae B
Semimajor axis (a)	47.8"
Inclination (i)	328°
Other designations
V* sig Aql, GCRV 12038, IDS 19342+0510 A, TD1 25149, 44 Aql, IRAS 19366+0517, TYC 487-3422-1, sig Aql, 2MASS J19391164+0523519, UBV M 23997, ADS 12737 A, GSC 00487-03422, N30 4347, UBV 21310, AG+05° 2775, HD 185507, PPM 168338, YZ 5 9427, BD+05° 4225, HGAM 768, ROT 3528, YZ 0 2219, CCDM J19392+0524A, HIC 96665, SAO 124903, CSI+05 4225 1, HIP 96665, SBC7 759, GC 27185, HR 7474.
Database references
SIMBAD	data
Database references
SIMBAD	data

Sigma Aquilae (σ Aql / σ Aquilae) is a binary star in the constellation Aquila. It is approximately 680 light years from Earth.

Sigma Aquilae is an eclipsing spectroscopic binary. Both components are detached blue-white B-type main sequence dwarfs which do not fill their Roche lobes. The mean apparent magnitude of the binary is +5.18. Because it is an eclipsing binary, σ Aquilae is also a variable star and its brightness varies by 0.2 magnitudes with a period equal to its orbital period of 1.95 days.