Astronomy:7 Aquilae

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Short description: Star in the constellation Aquila
7 Aquilae
7AqlLightCurve.png
A blue band light curve for 7 Aquilae, adapted from Machado et al. (2007)[1]
Observation data
Equinox J2000.0]] (ICRS)
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[2] mas
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 astronomical unit|AU away from the host star.[5]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 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. doi:10.1086/520062. Bibcode2007AJ....134..860F. 
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940  Gaia DR3 record for this source at VizieR.
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8 3.9 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. doi:10.1016/j.newast.2009.11.006. Bibcode2010NewA...15..397F. 
  4. 4.0 4.1 Houk, N.; Swift, C. (1999). "Michigan catalogue of two-dimensional spectral types for the HD Stars". Michigan Spectral Survey 5. Bibcode1999MSS...C05....0H. 
  5. 5.0 5.1 5.2 Cotten, Tara H.; Song, Inseok (July 2016). "A Comprehensive Census of Nearby Infrared Excess Stars". The Astrophysical Journal Supplement Series 225 (1): 24. doi:10.3847/0067-0049/225/1/15. 15. Bibcode2016ApJS..225...15C. 
  6. 6.0 6.1 "7 Aql". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=7+Aql.