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7 Aquilae

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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 18h 51m 05.40849s[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]
Distance359 ± 1 ly
(110.1 ± 0.3 pc)
Absolute magnitude (MV)1.22[3]
Details
Mass2.05[3][1] M
Radius2.73[5] R
Luminosity24[1] L
Surface gravity (log g)3.62[3] cgs
Temperature7,257[3] K
Metallicity [Fe/H]0.01[3] dex
Rotational velocity (v sin i)32[1] km/s
Age1.17[2] Gyr
Other designations
7 Aql, V1728 Aql, BD–03°4390, HD 174532, HIP 92501, SAO 142696[6]
Database references
SIMBADdata

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] This 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

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  1. ^ a b c d e f 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. ^ a b c d e f g h 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. ^ a b c d e f g h i j 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. ^ 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.
  5. ^ a b c 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. ^ a b "7 Aql". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-04-24.