Stephenson 2 DFK 49

If it was placed at the center of the Solar System, its photosphere would potentially approach or engulf Jupiter's orbit.

[8] A recent study on red supergiant mass loss rates and histories notes it as the most interesting object in the cluster, because its spectral energy distribution, which has a significant infrared excess, is similar to that of the famous and extreme red hypergiant VY Canis Majoris.

[2] An interesting note about Stephenson 2 DFK 49 is that it appears to be at the center of a bow-shock structure in infrared images.

Because of its properties and likely position on the H-R diagram, the authors of Davies 2007 stated that both it and Stephenson 2 DFK 1 warranted further studies, especially in terms of stellar evolution.

The study estimated Stephenson 2-11's luminosity at a much lower 132,000 L☉, using spectral energy distribution (SED).

Applying the Stefan-Boltzmann law, Stephenson 2 DFK 49’s radius would be 1,074 solar radii (747,000,000 kilometres; 4.99 astronomical units), making it one of the largest stars known.

Applying the Stefan-Boltzmann law, its radius would be 1,300 solar radii (900,000,000 kilometres; 6.0 astronomical units), larger than the other two estimates.

As a possible post-red supergiant star, Stephenson 2 DFK 49 likely experiences both constant and variable mass-loss rates.