18 Aquarii
| Observation data Epoch J2000 Equinox ICRS | |
|---|---|
| Constellation | Aquarius[1] |
| Right ascension | 21h 24m 11.49206s[2] |
| Declination | −12° 52′ 41.1928″[2] |
| Apparent magnitude (V) | 5.49[3] |
| Characteristics | |
| Evolutionary stage | main sequence[4] |
| Spectral type | F0 V[5] |
| B−V color index | +0.29[3] |
| Astrometry | |
| Radial velocity (Rv) | −3.0±6.9[1] km/s |
| Proper motion (μ) | RA: +89.60[2] mas/yr Dec.: +8.62[2] mas/yr |
| Parallax (π) | 21.23±0.29 mas |
| Distance | 154 ± 2 ly (47.1 ± 0.6 pc) |
| Absolute magnitude (MV) | 2.12[1] |
| Details | |
| Mass | 1.54[6] M☉ |
| Luminosity | 11.8[1] L☉ |
| Surface gravity (log g) | 3.98[7] cgs |
| Temperature | 7,194[7] K |
| Metallicity [Fe/H] | –0.16[7] dex |
| Rotational velocity (v sin i) | 138[8] km/s |
| Age | 480[6] Myr |
| Other designations | |
| 18 Aqr, BD−13°5923, FK5 1562, HD 203705, HIP 105668, HR 8187, SAO 164364[9] | |
| Database references | |
| SIMBAD | data |
18 Aquarii is a single,[10] yellow-white hued star in the equatorial constellation of Aquarius. The designation is from the catalogue of English astronomer John Flamsteed, first published in 1712. The star is faintly visible to the naked eye with an apparent visual magnitude of 5.49[3] and is located about 154 light-years (47 parsecs) from Earth.[2]
This is an F-type main sequence star with a stellar classification of F0 V.[5] It is an estimated 480[6] million years old and has a high rate of spin with a projected rotational velocity of 138 km/s.[8] The star has 1.54[6] times the mass of the Sun and is radiating 11.8[1] times the Sun's luminosity from its photosphere at an effective temperature of 7,194 K.[7]
References
- 1 2 3 4 5 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. XHIP record for this object at VizieR.
- 1 2 3 4 5 van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357, S2CID 18759600.
- 1 2 3 Johnson, H. L.; et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory, 4 (99): 99, Bibcode:1966CoLPL...4...99J.
- ↑ Zorec, J.; Royer, F. (2012). "Rotational velocities of A-type stars. IV. Evolution of rotational velocities". Astronomy and Astrophysics. 537: A120. arXiv:1201.2052. Bibcode:2012A&A...537A.120Z. doi:10.1051/0004-6361/201117691.
- 1 2 Houk, Nancy (1978), Michigan Catalogue of Two-dimensional Spectral Types for the HD Stars, vol. 4, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode:1988mcts.book.....H.
- 1 2 3 4 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.
- 1 2 3 4 Soubiran, C.; et al. (June 2010), "The PASTEL catalogue of stellar parameters", Astronomy and Astrophysics, 515: A111, arXiv:1004.1069, Bibcode:2010A&A...515A.111S, doi:10.1051/0004-6361/201014247, S2CID 118362423.
- 1 2 Royer, F.; Zorec, J.; Gómez, A. E. (February 2007), "Rotational velocities of A-type stars. III. Velocity distributions", Astronomy and Astrophysics, 463 (2): 671–682, arXiv:astro-ph/0610785, Bibcode:2007A&A...463..671R, doi:10.1051/0004-6361:20065224, S2CID 18475298.
- ↑ "18 Aqr". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-02-02.
- ↑ De Rosa, R. J.; Patience, J.; Wilson, P. A.; Schneider, A.; Wiktorowicz, S. J.; Vigan, A.; Marois, C.; Song, I.; MacIntosh, B.; Graham, J. R.; Doyon, R.; Bessell, M. S.; Thomas, S.; Lai, O. (2014), "The VAST Survey - III. The multiplicity of A-type stars within 75 pc", Monthly Notices of the Royal Astronomical Society, 437 (2): 1216, arXiv:1311.7141, Bibcode:2014MNRAS.437.1216D, doi:10.1093/mnras/stt1932.