The star 61 Cygni in the constellation Cygnus (The Swan) has the largest proper motion of any naked eye star at 5.3"/yr, about half that of Barnard's Star. The motion was first noted by Giuseppe Piazzi in 1804 (three years after he discovered Ceres) and the star acquired the nickname "Piazzi's Flying Star". It's distance was measured via parallax by Friedrich Bessel in 1836. Bessel's result was the first direct distance measurement for any star other than our sun. At 11.4 ly it is the 14th closest star system and the 5th closest naked-eye star, after Procyon.
61 Cygni is actually a double-star system with the two stars having a combined magnitude of 4.8. Separated by about 31" they are an easy target for small telescopes. Under fairly dark sqml=21.4 skies I was just barely able to make out this star with averted vision after a few minutes of letting my eyes adjust, so the "naked eye" designation is definitely a personal attribute. It was dead easy with a 2x54 binocular.
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Cygnus setting over Bristol Head. 61 Cyni is marked by the white circle. EM1iii + Leica 15mm f/1.7 + softon. ISO 1600, 60 s.
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E-P5 + Rokinon 135mm f/2. ISO 1600, 60 s. 2° field.
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61 Cygni. E-M5iii + AT60mmED f/6 refractor. ISO 1600, 10 s. 0.5° field.
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