Zeta Boötis

ζ Boötis
Location of ζ Boötis (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Boötes
ζ Boo
Right ascension 14h 41m 08.95158s
Declination +13° 43 41.8967
Apparent magnitude (V) 3.78 (4.46 + 4.55)
HIP 71759
Right ascension 14h 40m 42.39288s
Declination +13° 32 03.5621
Apparent magnitude (V) 5.925
Characteristics
ζ Boo
Spectral type A1V
U−B color index +0.05
B−V color index +0.05
HIP 71759
Spectral type F0V
B−V color index 0.227
Variable type δ Scuti
Astrometry
ζ Boo
Radial velocity (Rv)−8.5±0.6 km/s
Proper motion (μ) RA: +51.95 mas/yr
Dec.: −11.08 mas/yr
Parallax (π)18.56±0.76 mas
Distance176 ± 7 ly
(54 ± 2 pc)
Absolute magnitude (MV)+0.13
HIP 71759
Proper motion (μ) RA: +54.399 mas/yr
Dec.: −15.481 mas/yr
Parallax (π)19.3257 ± 0.0511 mas
Distance168.8 ± 0.4 ly
(51.7 ± 0.1 pc)
Absolute magnitude (MV)2.37
Orbit
Primaryζ Boo A
Companionζ Boo B
Period (P)125.04+0.24
−0.21
years
Semi-major axis (a)41.84+0.46
−0.44
 au
Eccentricity (e)0.98045
Inclination (i)125.88±0.16°
Longitude of the node (Ω)176.63±0.16°
Periastron epoch (T)2023.9548
Argument of periastron (ω)
(secondary)
62.08+0.13
−0.14
°
Details
ζ Boo A
Mass2.21+0.14
−0.05
 M
Radius2.6+0.3
−0.4
 R
Temperature8,800+1,000
−600
 K
Age560+150
−240
 Myr
ζ Boo B
Mass2.15+0.10
−0.03
 M
Radius2.4±0.3 R
Temperature8,750+800
−550
 K
Age560+150
−240
 Myr
HIP 71759
Mass1.79±0.29 M
Radius1.70±0.05 R
Luminosity9.01±0.22 L
Surface gravity (log g)4.23±0.08 cgs
Temperature7,660±107 K
Other designations
ζ Boo, 30 Boötis, BD+14°2770, GC 19777, HIP 71795, SAO 101145, ADS 9343, CCDM 14411+1344, WDS J14411+1344
A: HD 129247, HR 5478
B: HD 129246, HR 5477
HIP 71759: BD+14 2769, HD 129153, HR 5473, SAO 101137, TIC 119613557, TYC 917-1472-1
Database references
SIMBADdata
HIP 71759
SIMBADdata

Zeta Boötis is a binary star system in the constellation of Boötes that forms a triple star system with HIP 71759. Its name is a Bayer designation that is Latinized from ζ Boötis, and abbreviated Zeta Boo or ζ Boo. They have the Flamsteed designation 30 Boötis. This system is visible to the naked eye as a point of light with an apparent visual magnitude of +3.78. The individual magnitudes of the components differ slightly, with component A having a magnitude of 4.46 and component B at the slightly dimmer magnitude 4.55. The system is located at a distance of approximately 180 light years based on parallax, but is drifting closer to the Sun with a radial velocity of −9 km/s.