8 Aquilae
| Observation data EpochJ2000EquinoxJ2000 | |
|---|---|
| Constellation | Aquila |
| Right ascension | 18h51m22.15821s[2] |
| Declination | −03° 19′ 04.2851″[2] |
| Apparent magnitude(V) | 6.08[3] |
| Characteristics | |
| Spectral type | F0 IV[4]or F2 III[5] |
| U−Bcolor index | +0.06[6] |
| B−Vcolor index | +0.299±0.007[7] |
| Variable type | δ Sct[5] |
| Astrometry | |
| Radial velocity(Rv) | +11.8[3]km/s |
| Proper motion(μ) | RA:+2.019[2]mas/yr Dec.:−21.411[2]mas/yr |
| Parallax(π) | 12.0549 ± 0.0268mas |
| Distance | 270.6 ± 0.6ly (83.0 ± 0.2pc) |
| Absolute magnitude(MV) | 1.27[5] |
| Details | |
| Mass | 1.60[8]M☉ |
| Radius | 3.0[2]R☉ |
| Luminosity | 18.89[7]L☉ |
| Surface gravity(logg) | 3.88±0.14[8]cgs |
| Temperature | 7,395±251[8]K |
| Metallicity[Fe/H] | 0.14[5]dex |
| Rotational velocity(vsini) | 105[9]km/s |
| Age | 959[8]Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
8 Aquilaeis astarin theequatorialconstellationofAquila,[10]located 271light yearsaway from the Sun.8 Aquilaeis theFlamsteed designation.It can be viewed with the naked eye in good seeing conditions, appearing as a dim, yellow-white hued star with anapparent visual magnitudeof 6.08.[3]The star is moving further from the Earth with a heliocentricradial velocityof +12 km/s.[3]
Abt and Morrell (1995) found astellar classificationof F0 IV[4]for this star, suggesting it is anF-typesubgiant.In their 2010 study, Fox Machado et al. assigned a class of F2 III,[5]which matches anevolvedgiant star.Despite thespectral classifications,evolutionary models place the star towards the end of itsmain sequencelife, with an age of about a billion years.[8][2]
8 Aquilae is aDelta Scuti variablewith at least three overlapping pulsation frequencies, although the total amplitude of its brightness variations is only about 0.02 magnitudes.[5]It has a relatively high rotation rate, showing aprojected rotational velocityof 105 km/s.[9]It has 1.6[8]times themass of the Sunand is radiating 19[7]times theSun's luminosityfrom itsphotosphereat aneffective temperatureof about 7,395 K.[8]
References
[edit]- ^Machado, L. Fox; Michel, E.; Hernandez, F. Perez; Pena, J. H.; Li, M. A.; Pau, S.; Fernandez, A.; Michel, J. P.; Michel, R.; Pani, A. (August 2007). "Multisite Observations of δ Scuti Stars 7 Aql and 8 Aql (a New δ Scuti Variable): The Twelfth STEPHI Campaign in 2003".The Astronomical Journal.134(2): 860–866.arXiv:0706.0576.Bibcode:2007AJ....134..860F.doi:10.1086/520062.S2CID15349358.
- ^abcdefVallenari, A.; et al. (Gaia collaboration) (2023)."GaiaData Release 3. Summary of the content and survey properties ".Astronomy and Astrophysics.674:A1.arXiv:2208.00211.Bibcode:2023A&A...674A...1G.doi:10.1051/0004-6361/202243940.S2CID244398875. Gaia DR3 record for this sourceatVizieR.
- ^abcdWielen, R.; et al. (1999), "Sixth Catalogue of Fundamental Stars (FK6). Part I. Basic fundamental stars with direct solutions",Veroeffentlichungen des Astronomischen Rechen-Instituts Heidelberg,35(35), Astronomisches Rechen-Institut Heidelberg: 1,Bibcode:1999VeARI..35....1W.
- ^abAbt, Helmut A.; Morrell, Nidia I. (1995), "The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars",Astrophysical Journal Supplement,99:135,Bibcode:1995ApJS...99..135A,doi:10.1086/192182.
- ^abcdefFox Machado, L.; et al. (July 2010), "Strömgren photometry and spectroscopy of the δ Scuti stars 7 Aql and 8 Aql",New Astronomy,15(5): 397–402,arXiv:0912.2808,Bibcode:2010NewA...15..397F,doi:10.1016/j.newast.2009.11.006,S2CID119241648.
- ^Cousins, A. W. J. (1965), "Photometric Data for Stars in the Equatorial Zone (Eighth List)",Monthly Notes of the Astronomical Society of Southern Africa,24:120,Bibcode:1965MNSSA..24..120C.
- ^abcAnderson, 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,S2CID119257644.
- ^abcdefgDavid, 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,S2CID33401607.
- ^abRoyer, F.; et al. (2002), "Rotational velocities of A-type stars in the northern hemisphere. II. Measurement of v sin i in the northern hemisphere",Astronomy and Astrophysics,393(3): 897–911,arXiv:astro-ph/0205255,Bibcode:2002A&A...393..897R,doi:10.1051/0004-6361:20020943,S2CID14070763.
- ^ab"8 Aql".SIMBAD.Centre de données astronomiques de Strasbourg.RetrievedApril 25,2019.
