QS Aquilae

QS Aquilae

A visual band light curve for QS Aquilae. Adapted from Zasche et al. (2017)[1]
Observation data
Epoch J2000      Equinox J2000
Constellation Aquila
Right ascension 19h 41m 05.528s[2]
Declination +13° 48′ 56.45″[2]
Apparent magnitude (V) 5.988
Characteristics
Spectral type B5V
U−B color index −0.52
B−V color index −0.08
Variable type Eclipsing binary[3]
Astrometry
Radial velocity (Rv)−14.2 ± 2 km/s
Proper motion (μ) RA: −0.04 ± 0.60[2] mas/yr
Dec.: −11.47 ± 0.43[2] mas/yr
Parallax (π)0.49 ± 0.62 mas[2]
Orbit[3]
PrimaryQS Aquilae AB (eclipsing pair)
CompanionQS Aquilae C
Period (P)77.0±4.3 yr
Semi-major axis (a)0.111±0.045″
Eccentricity (e)0.947±0.038
Inclination (i)61.2±3.6°
Longitude of the node (Ω)144.5±5.1°
Periastron epoch (T)1962.3±2.3
Argument of periastron (ω)
(secondary)		336.8±4.7°
Orbit[3]
PrimaryQS Aquilae A
CompanionQS Aquilae B
Period (P)2.5132987±0.0000075 d
Semi-major axis (a)13.78±0.11 R⊙
Inclination (i)83.6±1.3°
Semi-amplitude (K1)
(primary)		73.98±0.33 km/s
Semi-amplitude (K2)
(secondary)		201.76±2.09 km/s
Other designations
KUI 93, QS Aql, BD+13° 4098, HD 185936, HIP 96840, HR 7486, WDS J19411+1349, 2MASS J19410553+1348565[4]
Database references
SIMBADdata

QS Aquilae is a triple or quadruple star system consisting of an eclipsing binary in a 2.5 day orbit around which a third star orbits in 77 years.[3] There is some indication that there is a fourth component with a period of roughly 18 years.[5] Located in the constellation Aquila, its visual magnitude varies from 5.93 to 6.06, making it barely visible to the naked eye.[6]

The star's variability was discovered photometrically by Paul Guthnick and Richard Prager in 1930. It was given its variable star designation in 1934.[7]

  1. ^ Cite error: The named reference Zasche was invoked but never defined (see the help page).
  2. ^ a b c d e Cite error: The named reference van Leeuwen2007 was invoked but never defined (see the help page).
  3. ^ a b c d Cite error: The named reference Zasche2017 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference Simbad was invoked but never defined (see the help page).
  5. ^ Heintze, J.R.W.; Hoekzema, Nico (1989). "The Algol-Type Binary QS AQL". International Astronomical Union Colloquium. 107: 344–345. doi:10.1017/s0252921100088011. ISSN 0252-9211.
  6. ^ Cite error: The named reference GCVS was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference Guthnick was invoked but never defined (see the help page).