70 Aquarii is a variable star located 425[2] light years away from the Sun in the equatorial constellation of Aquarius. It has the variable star designation FM Aquarii;[7] 70 Aquarii is the Flamsteed designation. It is near the lower limit of visibility to the naked eye, appearing as a dim, yellow-white hued star with a baseline apparent visual magnitude of 6.19.[3] This star is moving closer to the Earth with a heliocentric radial velocity of –5.8 km/s.[6]
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Aquarius |
| Right ascension | 22h 48m 30.21043s[2] |
| Declination | –10° 33′ 19.7143″[2] |
| Apparent magnitude (V) | 6.19[3] |
| Characteristics | |
| Evolutionary stage | main sequencec |
| Spectral type | F0 V[4] |
| B−V color index | +0.28[3] |
| Variable type | δ Sct[5] |
| Astrometry | |
| Radial velocity (Rv) | –5.8[6] km/s |
| Proper motion (μ) | RA: +31.535[2] mas/yr Dec.: +7.915[2] mas/yr |
| Parallax (π) | 7.6654 ± 0.0704 mas[2] |
| Distance | 425 ± 4 ly (130 ± 1 pc) |
| Absolute magnitude (MV) | +0.88[7] |
| Details | |
| Radius | 4.17+0.17 −0.23[2] R☉ |
| Luminosity | 44.8±0.5[2] L☉ |
| Surface gravity (log g) | 3.48[7] cgs |
| Temperature | 7,314+187 −144[2] K |
| Metallicity [Fe/H] | 0.02±0.15[8] dex |
| Rotational velocity (v sin i) | 110[9] km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
Werner Wolfgang Weiss discovered that 70 Aquarii was a variable star in 1977.[1] It was given its variable star designation in 1981.[11]
This is an F-type main-sequence star with a stellar classification of F0 V.[4] Located in the lower part of the instability strip, it is a Delta Scuti-type variable that ranges in brightness from magnitude 6.16 down to 6.19 with a period of 125 minutes (0.087 days).[5] The star has a high rate of spin, showing a projected rotational velocity of 110 km/s.[9] It has four[2] times the Sun's radius and is radiating 45[2] times the luminosity of the Sun from its photosphere at an effective temperature of around 7,314 K.[2]
References
edit- ^ a b Weiss, W. W. (November 1977). "HR 239 and HR 8676: Two delta Scuti-Type Variables". Information Bulletin on Variable Stars. 1364: 1. Bibcode:1977IBVS.1364....1W. Retrieved 16 October 2021.
- ^ a b c d e f g h i j k l 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 c Corben, P. M.; Stoy, R. H. (1968), "Photoelectric Magnitudes and Colours for Bright Southern Stars", Monthly Notes of the Astronomical Society of Southern Africa, 27: 11, Bibcode:1968MNSSA..27...11C.
- ^ a b Houk, N.; Swift, C. (1999), "Michigan catalogue of two-dimensional spectral types for the HD Stars", Michigan Spectral Survey, 5, Bibcode:1999MSS...C05....0H.
- ^ a b Samus, N. N.; et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1, 61 (1): 80–88, Bibcode:2017ARep...61...80S, doi:10.1134/S1063772917010085, S2CID 125853869.
- ^ a b Wilson, R. E. (1953), "General Catalogue of Stellar Radial Velocities", Carnegie Institute Washington D.C. Publication, Carnegie Institute of Washington, D.C., Bibcode:1953GCRV..C......0W.
- ^ a b c Paunzen, E.; et al. (September 2002), "On the Period-Luminosity-Colour-Metallicity relation and the pulsational characteristics of lambda Bootis type stars", Astronomy and Astrophysics, 392 (2): 515–528, arXiv:astro-ph/0207494, Bibcode:2002A&A...392..515P, doi:10.1051/0004-6361:20020854, S2CID 54666586
- ^ Gáspár, András; et al. (2016), "The Correlation between Metallicity and Debris Disk Mass", The Astrophysical Journal, 826 (2): 171, arXiv:1604.07403, Bibcode:2016ApJ...826..171G, doi:10.3847/0004-637X/826/2/171, S2CID 119241004.
- ^ a b Royer, F.; et al. (October 2002), "Rotational velocities of A-type stars in the northern hemisphere. II. Measurement of v sin i", Astronomy and Astrophysics, 393: 897–911, arXiv:astro-ph/0205255, Bibcode:2002A&A...393..897R, doi:10.1051/0004-6361:20020943, S2CID 14070763.
- ^ "70 Aqr". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-05-19.
- ^ Kholopov, P. N.; Samus, N. N.; Kukarkina, N. P.; Medvedeva, G. I.; Perova, N. B. (February 1981). "65th Name-List of Variable Stars". Information Bulletin on Variable Stars. 1921: 1–21. Bibcode:1981IBVS.1921....1K. Retrieved 18 November 2024.