19 Aquarii is a star in the zodiac constellation of Aquarius. With an apparent magnitude of about 5.7,[2] the star is barely visible to the naked eye as a white-hued star (see Bortle scale). Parallax estimates put it at a distance of about 260 light years away from the Sun.[1] The star is moving closer to the Earth with a heliocentric radial velocity of −21 km/s.[5]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aquarius |
| Right ascension | 21h 25m 13.01629s[1] |
| Declination | −09° 44′ 54.7923″[1] |
| Apparent magnitude (V) | +5.713[2] |
| Characteristics | |
| Spectral type | A8V[3] |
| B−V color index | +0.20[4] |
| Astrometry | |
| Radial velocity (Rv) | −20.6±1.8[5] km/s |
| Proper motion (μ) | RA: +25.943[1] mas/yr Dec.: −167.548[1] mas/yr |
| Parallax (π) | 12.5593 ± 0.1676 mas[1] |
| Distance | 260 ± 3 ly (80 ± 1 pc) |
| Absolute magnitude (MV) | 0.90[6] |
| Details | |
| Mass | 1.86[7] M☉ |
| Radius | 2.76+0.18 −0.16[1] R☉ |
| Luminosity | 26.1+0.4 −0.4[1] L☉ |
| Surface gravity (log g) | 4.13[7] cgs |
| Temperature | 8,078±275[7] K |
| Rotational velocity (v sin i) | 102[8] km/s |
| Age | 788[7] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This object is an A-type main-sequence star with a stellar classification of A8V.[3] It is around 788[7] million years old with a fairly fast rotation rate, as its projected rotational velocity is about 155 km/s,[8] so it must be rotating at least that fast. It has 1.86[7] times the mass of the Sun and 2.76[1] times the Sun's radius. 19 Aquarii is radiating 26[1] times the luminosity of the Sun from its photosphere at an effective temperature of 8,078 K.[7] Eggen has this star flagged as a blue straggler and a member of the HR1614 supercluster.[10]
References
edit- ^ a b c d e f g h i j Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b Høg, E.; et al. (2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27–L30. Bibcode:2000A&A...355L..27H.
- ^ a b Houk, N.; Swift, C. (1999). "Michigan catalogue of two-dimensional spectral types for the HD Stars, Vol. 5". Michigan Spectral Survey. 5: 0. Bibcode:1999MSS...C05....0H.
- ^ Johnson, H. L. (1966). "UBVRIJKL Photometry of the Bright Stars". Communications of the Lunar and Planetary Laboratory. 4: 99. Bibcode:1966CoLPL...4...99J.
- ^ a b 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.
- ^ Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. S2CID 119257644.
- ^ a b c d e f g David, Trevor J.; Hillenbrand, Lynne A. (2015). "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets". The Astrophysical Journal. 804 (2): 146. arXiv:1501.03154. Bibcode:2015ApJ...804..146D. doi:10.1088/0004-637X/804/2/146. S2CID 33401607.
- ^ a b Royer, F.; Zorec, J.; Gómez, A. E. (2007). "Rotational velocities of A-type stars". Astronomy and Astrophysics. 463 (2): 671. arXiv:astro-ph/0610785. Bibcode:2007A&A...463..671R. doi:10.1051/0004-6361:20065224. S2CID 18475298.
- ^ "* 19 Aqr". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 22 March 2017.
- ^ Eggen, Olin J. (October 1996). "Star Streams and Galactic Structure". Astronomical Journal. 112: 1595. Bibcode:1996AJ....112.1595E. doi:10.1086/118126.