It's not a single, solid "blanket", but rather a series of layers:

* Photosphere: This is the visible surface of the Sun, the layer that emits most of the light we see. It's where sunspots form.

* Chromosphere: This is a thin layer above the photosphere, characterized by a reddish glow due to hydrogen.

* Corona: This is the outermost layer of the Sun's atmosphere, extending millions of kilometers into space. It's extremely hot and is visible during a total solar eclipse.

So, while there isn't a single term for the entire vapor blanket, "solar atmosphere" encompasses all these layers.