Stephenson 2-18 (St2-18), also known as Stephenson 2 DFK 1 or RSGC2-18, is a red supergiant or red hypergiant star in the constellation of Scutum. It lies near the open cluster Stephenson 2, which is located about 6,000 parsecs (20,000 ly) away from Earth in the Scutum–Centaurus Arm of the Milky Way galaxy, and is assumed to be one of a group of stars at a similar distance. It is possibly among the largest known stars, and one of the most luminous red supergiants, with a possible radius around 2,150 times that of the Sun (R☉), which would correspond to a volume nearly 10 billion times that of the Sun.
Right ascension 18h 39m 02.3709s
Declination −06° 05′ 10.5357″
Spectral type ~M6
Distance 18,900 ly
Declination −06° 05′ 10.5357″
Spectral type ~M6
Distance 18,900 ly