Astronomy:12 Aquarii
Observation data Equinox J2000.0]] (ICRS) | |
---|---|
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 A: {{{names1}}} | |
12 Aqr B: {{{names2}}} | |
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]
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, doi:10.1051/0004-6361:20078357, Bibcode: 2007A&A...474..653V.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 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, doi:10.1111/j.1365-2966.2008.13596.x, Bibcode: 2008MNRAS.389..869E.
- ↑ 3.0 3.1 Houk, N.; Swift, C. (1999). "Michigan catalogue of two-dimensional spectral types for the HD Stars". Michigan Spectral Survey 5. Bibcode: 1999MSS...C05....0H.
- ↑ 4.0 4.1 4.2 4.3 4.4 4.5 4.6 Parsons, Sidney B. (May 2004), "New and Confirmed Triple Systems with Luminous Cool Primaries and Hot Companions", The Astronomical Journal 127 (5): 2915–2930, doi:10.1086/383546, Bibcode: 2004AJ....127.2915P.
- ↑ 5.0 5.1 Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters 32 (11): 759–771. doi:10.1134/S1063773706110065. Bibcode: 2006AstL...32..759G.
![]() | Original source: https://en.wikipedia.org/wiki/12 Aquarii.
Read more |