Lambda Cygni is a multiple star system in the northern constellation of Cygnus. Its name is a Bayer designation that is Latinized from λ Cygni and abbreviated λ Cyg or λ Cyg. With an apparent visual magnitude of 4.54, it is visible to the naked eye as a point of light. The system is located at a distance of approximately 770 light years based on parallax measurements.
Lambda Cygni is a multiple star, with components A, B, and C observed in the 19th century; the main component, A, is a spectroscopic binary itself with two components Aa and Ab reported at magnitudes 5.4 and 5.8 orbiting with a period of 12 years. Vizier catalog entry Component B has type B7V, magnitude 6.26, and separation 0.77" (about 180 AU based on parallax). Vizier catalog entry Component C has reported type K2III-IV, apparent magnitude 9.65, and separation about 85". Vizier catalog entry Recent observations indicate the presence of additional smaller companions D (about 50" from A), E (about 8" from C), and F (about 40" from C) all around apparent magnitude 14.
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