QS Aquilae is a triple or quadruple star system consisting of an
eclipsing binary
A binary star is a system of two stars that are gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved using a telescope as separate stars, in w ...
in a 2.5 day orbit around which a third star orbits in 77 years.
There is some indication that there is a fourth component with a period of roughly 18 years.
It is located in the constellation Aquila and is barely visible to the naked eye.
References
Aquila (constellation)
185936
Spectroscopic binaries
Algol variables
Eclipsing binaries
Aquilae, QS
7846
B-type main-sequence stars
096840
Durchmusterung objects
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