75 Cygni is a binary star^[9] system in the northern constellation of Cygnus. It is visible to the naked eye as a dim, reddish-hued point of light with an apparent visual magnitude of 5.09.^[2] The system is located at a distance of about 434 light years from the Sun, based on parallax, and is drifting closer with a radial velocity of −29 km/s.^[1]

The pair had an angular separation of 2.7″ as of 2008, with the companion having a visual magnitude of 10.7.^[9] The brighter magnitude 5.18^[9] primary is an aging red giant star with a stellar classification of M1IIIab.^[4] Having exhausted the supply of hydrogen at its core, it has expanded to around 46 times the radius of the Sun.^[7] It is a suspected variable star of unknown type and amplitude.^[5] The star is radiating 442 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 3,906 K.^[7]

It is likely that 75 Cygni is on the asymptotic giant branch, having exhausted its core helium,^[3] but there is a chance that it might be a higher-mass star on the red giant branch, before igniting its core helium.^[10]

An optical companion, with a spectral type of K, is about an arcminute away and has an apparent magnitude of 10.14.^[11]

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