How to see 61 Cygni
If brightness were the only real criteria, 61 Cygni would not be listed among the brightest stars. In fact, it takes some effort just to find it, because it is not much brighter than the faintest stars visible to the unaided human eye. However, it is among the most important of stars visible without optical aid. 61 Cygni is roughly halfway between easily seen Deneb, in Cygnus the Swan, and the end of the Swan’s east wing, the star Zeta Cygni (otherwise known as Geinah). Several other similarly dim stars are located nearby, and an accurate star chart is need to properly identify 61 Cygni. As with Cygnus itself, 61 Cygni is best observed in the fall and winter.
According to the Hipparcos space astrometry data, 61 Cygni has a visual magnitude of 5.2, borderline even under clear, dark skies, and not visible to the unaided eye at all from urban locations. While not actually the closest star to the sun (that honor goes to Alpha Centauri) 61 Cygni is just 11.4 light years distant, making it the fourth closest star visible to the unaided eye, after Alpha Centauri, Sirius, and Epsilon Eridani.
61 Cygni is classified as a K2V, which means that it is an orange (K2) “main sequence” (V) star. In fact, 61 Cygni is a binary star, although the double nature cannot be seen with just the eye.
From hottest to coolest, the spectral sequence is OBAFGKM, with the sun being a yellow G type star, compared to the two K-type components of 61 Cygni. Even taken together, the two stars of 61 Cygni cannot match our local star in total energy output.
History and Mythology
While 61 Cygni can boast no mythology, the ancients apparently leaving no written reference to it at all, its role in the history of astronomy is assured. As early as the late 1700s, astronomers recognized that its apparent motion among the stars is far greater than the average. Although this motion would take centuries to notice with the unaided eye, telescopic observations revealed a motion so startling that 61 Cygni became known as the “Flying Star.” This relatively fast motion indicates that the star is astronomically nearby, prompting German astronomer F. W. Bessel to use 61 Cygni to be the first star to have its distance measured by observation. As a result it is sometimes called “Bessel’s Star.”
61 Cygni’s position is RA: 21h 06m 51s, dec: +38° 44′ 29″