7 Aquilae

7 Aquilae

A blue band light curve for 7 Aquilae, adapted from Machado et al. (2007)[1]
Observation data Epoch J2000      Equinox J2000
Constellation	Aquila
Right ascension	18^h 51^m 05.40849^s[2]
Declination	−03° 15′ 40.0050″[2]
Apparent magnitude (V)	6.894[3]
Characteristics
Evolutionary stage	main sequence[2]
Spectral type	F0V[3] or F0IV[4]
B−V color index	+0.285[1]
Variable type	δ Sct[1]
Astrometry
Radial velocity (Rv)	−20.65[2] km/s
Proper motion (μ)	RA: −46.266[2] mas/yr Dec.: −59.024[2] mas/yr
Parallax (π)	9.0793 ± 0.0286 mas[2]
Distance	359 ± 1 ly (110.1 ± 0.3 pc)
Absolute magnitude (MV)	1.22[3]
Details
Mass	2.05[3][1] M☉
Radius	2.73[5] R☉
Luminosity	24[1] L☉
Surface gravity (log g)	3.62[3] cgs
Temperature	7,257[3] K
Metallicity [Fe/H]	0.01[3] dex
Rotational velocity (v sin i)	32[1] km/s
Age	1.17[2] Gyr
Other designations
7 Aql, V1728 Aql, BD–03°4390, HD 174532, HIP 92501, SAO 142696[6]
Database references
SIMBAD	data

7 Aquilae is a star in the equatorial constellation of Aquila,[6] located 359 light years away from the Sun. 7 Aquilae is the Flamsteed designation. It is visible to the naked eye as a faint, yellow-white hued star with a baseline apparent visual magnitude of 6.9. The star is moving closer to the Earth with a heliocentric radial velocity of −21 km/s.

Houk and Swift (1999) find a stellar classification of F0IV,[4] matching an F-type subgiant star that has exhausted the hydrogen at its core and is evolving into a giant. Fox Machado et al. (2010) found a class of F0V, suggesting it is still a main sequence star.[3] Ennio Poretti et al. discovered 7 Aquilae is a variable star while searching for targets to be observed by the CoRoT satellite, and published their discovery in 2003.[7] It is a pulsating variable star of the Delta Scuti type.[3] It has double[3] the mass of the Sun and 2.7[5] times the Sun's radius. The detection of an infrared excess suggests a debris disk with a mean temperature of 140 K is orbiting about 16.30 AU away from the host star.[5]

References

1. Fox Machado, L.; et al. (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. S2CID 15349358.
2. Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data 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. S2CID 244398875. Gaia DR3 record for this source at VizieR.
3. Fox Machado, L.; Alvarez, M.; Michel, R.; Moya, A.; Peña, J. H.; Parrao, L.; Castro, A. (2010). "Strömgren photometry and spectroscopy of the δ Scuti stars 7 Aql and 8 Aql". New Astronomy. 15 (5): 397. arXiv:0912.2808. Bibcode:2010NewA...15..397F. doi:10.1016/j.newast.2009.11.006. S2CID 119241648.
4. Houk, N.; Swift, C. (1999). "Michigan catalogue of two-dimensional spectral types for the HD Stars". Michigan Spectral Survey. 5. Bibcode:1999MSS...C05....0H.
5. Cotten, Tara H.; Song, Inseok (July 2016). "A Comprehensive Census of Nearby Infrared Excess Stars". The Astrophysical Journal Supplement Series. 225 (1): 24. arXiv:1606.01134. Bibcode:2016ApJS..225...15C. doi:10.3847/0067-0049/225/1/15. S2CID 118438871. 15.
6. "7 Aql". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-04-24.
7. Poretti, E.; Garrido, R.; Amado, P. J.; Uytterhoeven, K.; Handler, G.; Alonso, R.; Martín, S.; Aerts, C.; Catala, C.; Goupil, M. J.; Michel, E.; Mantegazza, L.; Mathias, P.; Pretorius, M. L.; Belmonte, J. A.; Claret, A.; Rodríguez, E.; Suarez, J. C.; Vuthela, F. F.; Weiss, W. W. (July 2003). "Preparing the COROT space mission: Incidence and characterisation of pulsation in the lower instability strip" (PDF). Astronomy and Astrophysics. 406: 203–211. doi:10.1051/0004-6361:20030711. Retrieved 22 November 2024.