Beta Delphini

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**Beta Delphini A/B**
Observation data Epoch J2000
Beta Delphini
Constellation (pronunciation)	Delphinus
Right ascension	20h 37m 32.9411s
Declination	+14° 35' 42.313"'
Apparent magnitude (V)	3.632
Characteristics
Spectral type	F5 IV
U-B color index	?
B-V color index	?
Variable type	None
Astrometry
Radial velocity (R_v)	-22.7 km/s
Proper motion (μ)	RA: 118.28 mas/yr Dec.: -47.65 mas/yr
Parallax (π)	33.49 ± 0.88 mas
Distance	97 ± 3 ly (29.9 ± 0.8 pc)
Absolute magnitude (M_V)	4.044
Details
Mass	> 2 / < 2 M_☉
Radius	? R_☉
Surface gravity (log g)	?
Luminosity	18 / 8 L_☉
Temperature	? K
Metallicity	?
Rotation	?
Age	? years
Visual binary orbit
Companion	Beta Delphini B
Period (P)	26.7 yr
Semimajor axis (a)	8 - 18 AU"
Eccentricity (e)	0
Inclination (i)	0°
Longitude of the node (Ω)	0°
Periastron epoch (T)	0
Other designations
2E 4395, JP11 3257, TYC 1100-1720-1, bet Del, GC 28709, 2MASS J20373291+1435421, UBV 17888, 6 Del, GCRV 12902, N30 4554, UBV M 25011, BU 151AB, PLX 4906, BU 151, GSC 01100-01720, ROT 3004, YZ 14 8041, ADS 14073 AB, HIC 101769, 1RXS J203732.7+143537, BD+14° 4369, HIP 101769, SAO 106316, CCDM J20375+1436AB, HR 7882, SBC7 821, CSI+14° 4369 1, IDS 20328+1415, 2E 2035.2+1425, IRC +10473, TD1 27036.
Database references
SIMBAD	data

Beta Delphini, also known as Beta Del, is a multiple star in the constellation Delphinus. As a practical joke, the astronomer Niccolò Cacciatore gave it the name Rotanev, which is a reversal of his Latinized family name, Venator. The star has five components; components A and B are a physical binary; C, D, and E are optical.

**Beta Delphini C/D/E**
Observation data Epoch J2000.0 (ICRS)
Constellation (pronunciation)	Delphinus
Right ascension	20^h 37^m 33.7^s/30.9^s/25.3^s
Declination	+14° 35′ 33″ +14° 36′ 17″ +14° 35′ 46″
Apparent magnitude (V)	13.1/11.0/unknown
Other designations
CCDM J20375+1436C/D/E; also, see designations for Beta Delphini A/B