12 Aquarii

Last updated
12 Aquarii
Observation data
Epoch J2000       Equinox J2000
Constellation Aquarius
Right ascension  21h 04m 04.72438s [1]
Declination −05° 49 23.0347 [1]
Apparent magnitude  (V)5.67 (5.88 + 7.55) [2]
Characteristics
Spectral type K0/1 III + A3 V [3] or G4 II + A3+ + (A4) [4]
Astrometry
Radial velocity (Rv)+1.1±0.3 [5]  km/s
Proper motion (μ)RA: +20.35 [1]   mas/yr
Dec.: -6.67 [1]   mas/yr
Parallax (π)6.50 ± 0.88 [1]   mas
Distance approx. 500  ly
(approx. 150  pc)
Absolute magnitude  (MV)0.1 + 1.4 + 1.5 [4]
Details
12 Aqr Aa/Ab
Mass 2.6/2.0 [4]   M
Temperature 5,012/8,511 [4]   K
12 Aqr B
Mass 1.9 [4]   M
Temperature 8,318 [4]   K
Other designations
12 Aqr, BD−06°5664, HIP  103981, ADS  14592, CCDM J21041-0549AB, WDS J21041-0549AB
12 Aqr A: HD  200497, HR  8059, SAO  145065
12 Aqr B: HD  200496, HR  8058, SAO  145064
Database references
SIMBAD 12 Aqr
12 Aqr A
12 Aqr B

12 Aquarii is a triple star [2] system in the zodiac constellation of Aquarius. 12 Aquarii is the Flamsteed designation. It is visible to the naked eye as a dim star with an apparent visual magnitude of 5.67. [2] Parallax measurements by Hipparcos puts it at a distance of some 500 light-years, or 150 parsecs away. [1] The system is moving further from the Earth with a heliocentric radial velocity of +1.1 km/s. [5]

The magnitude 5.88 primary, [2] component A, is itself a binary star with a separation of 0.05 0.07″ and an orbital period of around 18.5 yr. The brighter member of this duo is a G-type bright giant with a stellar classification of G4 II and 2.6 times the mass of the Sun. Its companion is an early A-type star with double the mass of the Sun. [4] The tertiary component B is magnitude 7.55 [2] A-type main-sequence star [3] at a separation of 2.44″ from the primary. [2]

Related Research Articles

Epsilon Aquarii star in the constellation Aquarius

Epsilon Aquarii, Latinized from ε Aquarii, is a single star in the equatorial zodiac constellation of Aquarius, located near the western constellation border with Capricornus. It has the proper name Albali, now formally recognized by the IAU. This is a white-hued star that is visible to the naked eye with an apparent visual magnitude of 3.77. Based upon parallax measurements taken during the Hipparcos mission, it is located at a distance of approximately 208 light-years (64 pc) from the Sun with an absolute magnitude of −0.46. The star is drifting closer with a radial velocity of −15 km/s.

Iota Tauri star in the constellation Taurus

Iota Tauri, Latinized from ι Tauri, is a white-hued star in the zodiac constellation Taurus and an outlying member of the Hyades star cluster. It is visible to the naked eye with an apparent visual magnitude of 4.62, and is located at an estimated distance of about 173 light years based upon parallax measurements. The star is moving away from the Sun with a radial velocity of +38 km/s.

Theta Volantis star

Theta Volantis is a solitary star in the southern constellation of Volans. Based upon parallax measurements, is approximately 240 light years from the Sun. It has an apparent visual magnitude of 5.19, which is bright enough to be faintly visible to the naked eye.

Psi<sup>3</sup> Aquarii Binary star in the constellation Aquarius

Psi3 Aquarii, Latinized from ψ3 Aquarii, is the Bayer designation for a visual binary star system in the constellation of Aquarius. It has an apparent visual magnitude of 4.98, which is bright enough to be seen with the naked eye. Parallax measurements give a distance estimate of roughly 262 light-years.

86 Aquarii Binary star in the constellation Aquarius

86 Aquarii is a binary star system in the equatorial constellation of Aquarius. 86 Aquarii is the Flamsteed designation, though it also bears the Bayer designation c1 Aquarii. It is faint but visible to the naked eye with an apparent visual magnitude of +4.47. Based upon parallax measurements, the distance to this star is about 220 light-years.

101 Aquarii Star in the constellation Aquarius

101 Aquarii is a star in the equatorial constellation of Aquarius. 101 Aquarii is the Flamsteed designation, although it also bears the Bayer designation b3 Aquarii. The combined apparent visual magnitude of the pair is 4.71, which is bright enough to be seen with the naked eye from the suburbs. The distance of this star from Earth is estimated as 290 light-years based upon parallax measurements.

89 Aquarii Binary star in the constellation Aquarius

89 Aquarii is a binary star system in the equatorial constellation of Aquarius. 89 Aquarii is the Flamsteed designation, though it also bears the Bayer designation c3 Aquarii. The apparent visual magnitude of +4.69 is bright enough to be seen with the naked eye. Its distance from Earth is roughly 500 light-years (150 pc), based upon parallax measurements with an 11% margin of error.

97 Aquarii is a binary star system in the equatorial constellation of Aquarius. 97 Aquarii is the Flamsteed designation. The combined apparent visual magnitude of the system is 5.20; the brighter star is magnitude 5.59 while the companion is magnitude 6.72. Based upon an annual parallax shift of 15.30 milliarcseconds, this system is at a distance of around 210 light-years from Earth.

42 Aquarii is a single star located 447 light years away from the Sun in the zodiac constellation of Aquarius. 42 Aquarii is its Flamsteed designation. It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 5.34. This object is moving further from the Sun with a heliocentric radial velocity of around +13 km/s.

5 Aquarii is a single star in the zodiac constellation of Aquarius, located about 830 light years away from the Sun, based on parallax. 5 Aquarii is the Flamsteed designation. It is visible to the naked eye as a faint, blue-white hued star with an apparent visual magnitude of 5.55. This object is moving closer to the Earth with a heliocentric radial velocity of −3 km/s.

51 Aquarii is a binary star system located around 410 light years away from the Sun in the equatorial constellation of Aquarius. 51 Aquarii is its Flamsteed designation. It is visible to the naked eye as a dim, yellow-white hued star with a combined apparent visual magnitude of 5.78. The system is moving further from the Earth with a heliocentric radial velocity of +6 km/s.

15 Aquarii, abbreviated 15 Aqr, is a single, blue-white star in the zodiac constellation of Aquarius. 15 Aquarii is the Flamsteed designation. It is a dim star that is just visible to the naked eye under good viewing conditions, having an apparent visual magnitude of 5.83. Based upon an annual parallax shift of 4.6 mas, it is located around 710 light years away. At that distance, the visual magnitude is diminished by an extinction of 0.18 due to interstellar dust. It is moving closer to the Earth with a heliocentric radial velocity of −9 km/s. Relative to its neighbors, 15 Aqr has a peculiar velocity of 28.7+2.9
−3.1
 km/s
and may be a runaway star.

Omega<sup>2</sup> Aquarii Star in the constellation Aquarius

Omega2 Aquarii, Latinized from ω2 Aquarii, is the Bayer designation for a triple star system in the equatorial constellation of Aquarius. It can be seen with the naked eye, having an apparent visual magnitude of 4.49. The approximate distance to this star, 149 light-years, is known from parallax measurements taken during the Hipparcos mission.

2 Centauri is a single star in the southern constellation of Centaurus, located approximately 183 light years from Earth. It has the Bayer designation g Centauri; 2 Centauri is the Flamsteed designation. This object is visible to the naked eye as faint, red-hued star with an apparent visual magnitude of 4.19. It is moving away from the Earth with a heliocentric radial velocity of +41 km/s. The star is a member of the HD 1614 supercluster.

HD 157753 is giant star in the southern constellation of Ara. It may be an astrometric binary, and it has a faint, magnitude 13 companion at an angular separation of 31.5″ along a position angle of 356°.

HD 34557 is a double star in the northern constellation of Auriga. The fainter star has an angular separation of 0.380″ from the primary component. They have a combined apparent magnitude of 5.52, making HD 34557 faintly visible to the naked eye from dark skies. Based upon parallax measurements made with the Hipparcos satellite, this system is roughly 280 light years away. The primary component is spinning rapidly, with a projected rotational velocity of 217 km/s. It has a stellar classification of A3V, making it an A-type main sequence star.

HD 130917 is a single star in the northern constellation of Boötes. It is an A-type main sequence star with a stellar classification of A4V. At an apparent magnitude of 5.80, it is visible to the naked eye.

4 Scorpii star in the constellation Scorpius

4 Scorpii is a single star in the southern zodiac constellation of Scorpius. With an apparent visual magnitude of +5.6, it is dimly visible to the naked eye under good viewing conditions. The distance to this star can be estimated from its annual parallax shift of 7.99±0.77 mas, which yields a value of around 410 light years. It is moving closer to the Sun with a heliocentric radial velocity of −29 km/s and will reach perihelion in about two million years at an estimated distance of 280 ly (86 pc).

Delta1 Gruis, Latinized from δ1 Gruis, is a candidate binary star system in the constellation Grus. With a peak apparent visual magnitude of 3.97, it is bright enough to be seen with the naked eye at night. The distance to this system, as determined using an annual parallax shift of 10.54 mas as seen from the Earth, is around 309 light years. It is gradually moving away from the Sun with a radial velocity of +4.9 km/s.

Sigma2 Gruis is a binary star system in the southern constellation of Grus. Its apparent visual magnitude is 5.86. The pair had an angular separation of 2.7 arc seconds along a position angle of 265°, as of 1991. Located around 215 ly (66 pc) distant, the white-hued primary component is an A-type main-sequence star of spectral type A1V, a star that is currently fusing its core hydrogen.

References

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  2. 1 2 3 4 5 6 Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv: 0806.2878 , Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID   14878976.
  3. 1 2 Houk, N.; Swift, C. (1999). "Michigan catalogue of two-dimensional spectral types for the HD Stars". Michigan Spectral Survey. 5. Bibcode:1999MSS...C05....0H.
  4. 1 2 3 4 5 6 7 Parsons, Sidney B. (May 2004), "New and Confirmed Triple Systems with Luminous Cool Primaries and Hot Companions", The Astronomical Journal, 127 (5): 2915–2930, Bibcode:2004AJ....127.2915P, doi: 10.1086/383546 .
  5. 1 2 Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv: 1606.08053 . Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID   119231169.