Topic summary
NML Cygni
NML Cygni or V1489 Cygni (abbreviated to NML Cyg or V1489 Cyg) is a redhypergiant or red supergiant (RHG or RSG) in the constellationCygnus. It is one of the largest known stars, and is also one of the most luminous and massive cool hypergiants, as well as one of the most luminous stars in the Milky Way.
The distance of NML Cygni from Earth is estimated to be around 1.6 kpc, about 5,300 light-years. It is a part of the Cygnus OB2association, one of the closest massive associations to the Sun, spanning nearly 2° on the sky or ~30 pc in radius at the distance of 1.74±0.2 kpc. Based on the estimated distance and an upper limit of its angular diameter of 7.8±0.64 milliarcseconds, NML Cygni's physical radius is estimated to be no more than 1,350 R☉. If placed at the center of the Solar System, its surface would potentially extend past the orbit of Jupiter.