HD 192685

HD 192685, also known as QR Vulpeculae or HR 7739, is a binary star about 1,000 ly away in the Vulpecula constellation. It is visible to the naked eye.

Description

In 1982 Krešimir Pavlovski and Hrvoje Božić announced their discovery that HD 192685 is a variable star. It was given its variable star designation, QR Vulpeculae, in 1985. HD 192685 varies slightly in brightness and is classified as a γ Cassiopeiae variable.
The stellar components have a projected separation of 70 astronomical units and have an estimated orbital period of 217 years. Component A is a Be star with a spectral type of B3Ve, having a mass 4.7 times that of the Sun, while component B has a class of A3V and is 1.8 times as massive as the Sun.
In July 1982, HD 192685 was observed to have its Hα spectral line, previously a broad absorption line, in emission with a central absorption core, and it was classified as a Be star. In late 1982 the emission increased in strength and the star brightened rapidly and briefly by over 0.1 magnitudes.
HD 192685 has excess infrared emissions which are interpreted to be free-free radiation in the gas surrounding the star.