e/IM Pegasi

Information
has gloss	eng: IM Pegasi is a variable binary star system approximately 329 light-years away in the constellation of Pegasus. With an apparent magnitude of 5.65, it is visible to the naked eye. The wide public awareness of it, however, is due to its use as the guide star for the Gravity Probe B general relativity experiment. It was chosen for this purpose because its microwave radio emissions are observable with a large radio telescope network on the ground in such a manner that its precise position can be related by interferometry to distant quasars.
lexicalization	eng: IM Pegasi
instance of	(noun) a system of two stars that revolve around each other under their mutual gravitation binary star, double star, binary