Stephenson 2 DFK 49

Stephenson 2 DFK 49 or St2-11 is a putative post red supergiant^[3] star in the constellation Scutum, in the massive open cluster Stephenson 2. It is possibly one of the largest known stars with a radius estimated to be between 1,074 solar radii (747,000,000 kilometres; 4.99 astronomical units)^[2] to 1,300 solar radii (900,000,000 kilometres; 6.0 astronomical units),^[3] corresponding to volumes of 1.2 and 2.2 times that of the Sun respectively. If it was placed at the center of the Solar System, its photosphere would potentially approach or engulf Jupiter's orbit. It loses mass at a very high rate, resulting in large amounts of infrared excess.