Zeta Aquarii

ζ Aquarii
Location of ζ Aquarii (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Aquarius
Right ascension 22h 28m 49.90685s[1]
Declination –00° 01′ 11.7942″[1]
Apparent magnitude (V) 3.65[2] (4.42 / 4.51)[3]
Characteristics
Spectral type F3 V + F6 IV[3]
U−B color index –0.01[2]
B−V color index +0.40[2]
Astrometry
Radial velocity (Rv)+24.9/+28.9[4] km/s
Proper motion (μ) RA: +182.92[1] mas/yr
Dec.: +50.36[1] mas/yr
Parallax (π)35.50 ± 1.26 mas[1]
Distance92 ± 3 ly
(28.2 ± 1.0 pc)
Absolute magnitude (MV)1.15[5]
Orbit[6]
Primaryζ Aqr Aa
Companionζ Aqr Ab
Period (P)25.95 ± 0.048 yr
Semi-major axis (a)0.385″
Eccentricity (e)0.872 ± 0.006
Inclination (i)11.8 ± 6.7°
Longitude of the node (Ω)293.7 ± 74°
Periastron epoch (T)B 2006.52 ± 0.13
Argument of periastron (ω)
(secondary)		100.9 ± 73°
Orbit[7]
Primaryζ Aqr A
Companionζ Aqr B
Period (P)540 ± 15 yr
Semi-major axis (a)3.496 ± 0.046″
Eccentricity (e)0.419 ± 0.011
Inclination (i)142.0 ± 0.4°
Longitude of the node (Ω)131.3 ± 0.8°
Periastron epoch (T)B 1981.50 ± 0.58
Argument of periastron (ω)
(secondary)		269.3 ± 1.7°
Details
ζ Aqr A
Mass1.4 / 0.6[7] M☉
Metallicity [Fe/H]–0.13[5] dex
Rotational velocity (v sin i)62[8] km/s
Age1.0[5] Gyr
ζ Aqr B
Mass1.4[7] M☉
Rotational velocity (v sin i)56[8] km/s
Other designations
55 Aquarii, ADS 15971, BD−00°4365, HIP 110960.
ζ Aqr A: ζ2 Aquarii, Zeta2 Aquarii, HD 213052, HR 8559, SAO 146108.
ζ Aqr B: ζ1 Aquarii, Zeta1 Aquarii, HD 213051, HR 8558, SAO 146107.
Database references
SIMBADζ Aqr
ζ Aqr A
ζ Aqr B

Zeta Aquarii (ζ Aquarii, ζ Aqr) is the Bayer designation for a triple star system,[7] the central star of the "water jar" asterism[9] in the equatorial constellation of Aquarius. The combined apparent visual magnitude of this system is 3.65,[2] which is readily visible to the naked eye. Parallax measurements yield a distance estimate of around 92 light-years (28 parsecs) from Earth.[1]

  1. ^ a b c d e f Cite error: The named reference aaa474_2_653 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference aass34_1 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference pasp122_898_1483 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference wilson1953 was invoked but never defined (see the help page).
  5. ^ a b c Cite error: The named reference aaa418_989 was invoked but never defined (see the help page).
  6. ^ "Sixth Catalog of Orbits of Visual Binary Stars". United States Naval Observatory. Archived from the original on 1 August 2017. Retrieved 14 June 2017.
  7. ^ a b c d Cite error: The named reference Tokovinin2016 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference coapa239_1 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference dibon_smith was invoked but never defined (see the help page).