this system to the Sun, it is a frequent target of interest for astronomers. Both stars were selected by NASA as "Tier 1" targets for the proposed optical Space Interferometry Mission. This mission is potentially capable of detecting planets with as little as 3 times the mass of the Earth at an orbital distance of 2 AU from the star. Measurements of this system appeared to have detected an excess of far infrared radiation, beyond what is emitted by the stars. Such an excess is sometimes associated with a disk of dust, but in this case it lies sufficiently close to one or both of the stars that it has not been resolved with a telescope. A 2011 study using the Keck Interferometer Nuller failed to detect any exozodiacal dust around 61 Cygni A. Object for biosignature research The two stars are among five (all nearby star) paradigms listed among those K-type stars of a type in a 'sweet spot' between Sun-analog stars and M stars for the likelihood of evolved life, per analysis of Giada Arney from NASA's Goddard Space Flight Center. See also List of nearest stars Barnard's Star Notes References External links Cygnus (constellation) Binary stars BD+38 4343 and BD+38 4344 K-type main-sequence stars Cygni, 61 0820 201091 2 High-proper-motion stars 104214 and 104217 8085 and 8086 Cygni, V1803 BY Draconis variables Discoveries by Giuseppe Piazzi